Good morning. Thank you for joining us to hear our prepared remarks on General Mills' 2nd quarter fiscal 2021 earnings. Later this morning, we will hold a live question and answer session on today's results, which you can hear via webcast on our Investor Relations website. In a moment, I'll turn the call over to Jeff Harmening, our Chairman and CEO and Kofi Brutes, our CFO. But before I do, let me first touch on a few items.
On our website, you will find our Q2 press release that posted this morning, along with a copy of the presentation and a transcript of these remarks. It's important to note that today's remarks will include forward looking statements that are based on management's current views and assumptions, including facts and assumptions Jeff and Kofi will share related to the potential impact of the COVID-nineteen pandemic on our results in fiscal 2021. The second slide in today's presentation lists several factors that could cause our future results to be different than our current estimates. And with that, I'll turn you over to my colleagues beginning with Jeff. Thanks, Jeff, and good morning, everyone.
Today's key messages are listed on Slide 4. We executed very well again in the Q2, driving strong performance on the top and bottom lines. As the pandemic continues to significantly impact our key markets around the world, we're focusing on what we can control, keeping our manufacturing facilities operating safely with minimal disruption, partnering with suppliers and retailers to ensure supply of our products and delivering consumer solutions that meet their current needs through our trusted leading brands. Our strong execution has generated winning and market performance. Our retail sales are outpacing our competition, translating into broad based market share gains across our major markets.
With excellent performance through the first half, we remain on track to deliver our 3 key priorities for fiscal 2021, competing effectively everywhere we play, fueling investment in our brands and capabilities, and continuing to reduce our leverage. Because of the current state of the virus in the U. S. And across our major markets, we expect consumer demand for food at home will remain elevated relative to pre pandemic levels through the remainder of our fiscal 2021. With elevated demand and continued best in class execution, we're forecasting continued strong top and bottom line growth in the Q3.
And while uncertainty with the virus makes it difficult to forecast full year demand, we now expect our full year fiscal 2021 adjusted operating profit margin to be in line or better than last year based on our first half results that were somewhat ahead of our expectations. You can see our enterprise second quarter financial performance on Slide 5. Strong demand for food at home and continued market share gains helped drive 7% growth in organic net sales in the quarter. Constant currency adjusted operating profit was up 6%, reflecting strong net sales growth, higher input costs and a double digit increase in media investment. Constant currency adjusted diluted earnings per share were up 9% in the quarter and were up 17% in the first half.
As I mentioned upfront, we are focused on 3 priorities outlined on Slide 6 that will drive strong performance in fiscal 2021 while advancing our long term strategies. And I'm pleased to say that we're delivering on all three. We continue to compete effectively everywhere we play. Through the first half, we've driven broad based market share gains, including holding or growing share in 5 of our 6 largest markets. We're driving efficiency from our holistic margin management and strategic revenue management initiatives, which we refer to as and SRM respectively, and we're benefiting from volume leverage allowing us to offset higher cost to service elevated demand and providing fuel for investments in our brand and capabilities.
Finally, we've made further progress on reducing our debt leverage in the Q2. Our strong balance sheet position allows us to recently resume dividend growth and increases our flexibility for bolt on M and A or share buybacks at the right time. We are very much in the middle of the pandemic in most of our markets and expect to be for some time to come. The specific status of the virus and resulting consumer behaviors vary across our key markets. In the United States, case counts have been on the rise and demand for our food at home food categories has grown at a consistent high single digit rate in recent months, while away from home demand has consistently been down low double digits during that time.
In France and the U. K, the recent surge in cases occurred about a month earlier than the U. S. And we saw at home category growth step up as consumer restrictions were put in place. In Brazil, very high at home demand in Q1 moderated in Q2 as consumer restrictions eased.
And in China, the virus is relatively well controlled. While consumer traffic is much closer to normal in our shops, we've seen demand for at home food, including Wanchai Fairy Frozen Dumplings, remain notably above pre pandemic levels. This situation remains dynamic across each of these markets and we are staying agile to meet demand as it evolves. We along with the rest of the world are highly encouraged by recent food demand will remain robust relative to pre pandemic levels for the remainder of our fiscal 2021. As we take a step back from the day to day dynamic, we see consumer behaviors evolving in ways that we think will stick beyond the pandemic.
First, we think consumers will be eating more at home in the new normal. Many consumers have told us that they're enjoying the benefits of home centricity in their lives, including flexible work environments, more family time and more balance driving a better quality of life. We expect more time at home, including more work from home to be an ongoing part of consumer routines, meaning more opportunities for at home eating occasions. We also believe beyond the pandemic and what we've learned from past recessions is that the first and most significant way consumers economize in their food budgets is by eating more at home. For example, in the great recession of 2,008 to 2010, we saw growth for our at home categories accelerate by about 2 points.
Importantly, we were able to drive similar acceleration for our business, allowing us to hold market share through that period. With our improved capabilities and strategic revenue management and personalized marketing, we're in an even better position to adapt our offerings and connect with consumers in meaningful ways during difficult economic times. 2nd, since the onset of the pandemic, consumers have been seeking brands they know and trust to bring a sense of normalcy and comfort to their lives. We've seen evidence that our ongoing work to renovate the taste, nutrition and convenience of our products in addition to our continued focus on brand building and innovation is building loyalty with these new and returning consumers that will benefit our brands over the long term. 3rd, we've seen a dramatic acceleration of food e commerce adoption and a continued shift where consumers getting their news, information and other media through digital means.
And it's clear that these changes will have lasting impact beyond the current environment. We'll benefit from these changes by leveraging our advantaged digital capabilities, including significant first party consumer interactions to drive differential growth. And we'll benefit from our e commerce capability and strategic customer partnerships, which have helped us over index online and market share compared to bricks and mortar outlets. With those consumer changes in mind, we're taking actions to drive success today and to ensure we win in the long term. These include: boldly building our brands with remarkable brand experiences supported by appropriate levels of spending relentlessly innovating to delight consumers and meet their evolving needs and unleashing our scale through capabilities that drive competitive advantage, including data and analytics, e commerce, SRM and Let me share some examples of how these efforts are coming to life in fiscal 2021.
Creating and maintaining vibrant consumer relevant brands is central to General Mills' long term success. In challenging times, it's as important as ever that we gain deep empathy for consumers' lives and create food and brand experiences to solve their problems and bring them joy. We're focused on engaging consumers with messages that are relevant to their current situation. For example, as many consumers are experiencing a non traditional holiday season, our marketing has been respectful and apathetic to what is a more challenging time. In the U.
S, our Betty Flip and Crocker campaign encourages families that they can create the solutions they need to make cooking and baking easy, affordable, and full of joy this holiday season. Pillsbury has also made it their mission to help deliver a holiday season that lets you enjoy the few food you love while making memories at home. These campaigns leverage traditional and digital media and we're leading into our bettycrocker.com andpillsbury.comfood websites to deliver recipe ideas and build consumer connections that drive growth for our brands. Our old El Paso team showcased our ability to act as a global force for good by partnering with tennis stars from around the world in the MessFreeChallenge, donating more than 100,000 meals and driving awareness for our innovative Old El Paso Tortilla Pockets and Bowls. Yoplait recognizes that kids today may be lacking the physical play they are used to.
So in partnership with Jennifer Lopez and her kids, Yoplait is challenging families to get moving fueled by the calcium in Yoplait yogurts to be healthy, active and strong. And finally, addressing heart health remains critical for many consumers, but can feel overwhelming in today's world, which is why Cheerios will double down on the success of last year's heart health campaign by approaching heart health with positivity and joy during heart health month this February. These messages are resonating with consumers. We continue to drive household penetration growth ahead of our competition and our new consumers are satisfied with our products with General Mills repeat rates outpacing our categories so far this year. We've also been pleased with our innovation performance in fiscal 2021.
We launched a number of successful new products in the first half, including Cinnamon Cheerios, the top new item in the U. S. Cereal category, convenient new Progreso Toppers, Nature Valley packed sustained energy bars and our relaunch Dunkaroo snacks and Old El Paso Tortilla Pockets, which are helping drive tremendous growth for the brand in Europe since they launched this summer. We also have an exciting innovation lineup for the back half of fiscal 2021 as well. In the U.
S, we're launching multi grain Cheerios with strawberries, delivering more great tasting common sense nutrition to the Cheerios franchise. And our new remix cereal lineup features multi texture, multi flavor mashups of tasty cereal pieces designed to further expand the category into the snacking occasion. In U. S. Yogurt, our new ratio protein line is a 2nd dairy snack to launch under the ratio brand, delivering 25 grams of protein with only 3 grams of sugar.
We continue to bring news to the snacking aisle including new Nature Valley Protein Crunch Bars at retail outlets and Muddy Buddy Pretzel Bites in the convenience store channel. And we have a full innovation slate outside North America, including the expansion of premium Wanchai Ferry Soup Dumplings in China and new indulgent Haagen Dazs ice cream flavors, including Belgian chocolate and hazelnut and dark chocolate and caramelized almond varieties, which we'll be launching across our international markets. As you saw in this morning's results, our Pet segment is performing exceptionally well with organic net sales up 18% this quarter and segment operating profit increasing 48%. We left our significant food, drug and mass channel expansion 9 months ago and the blue brand continues to win with pet parents as we drive awareness and educate them about the benefits of wholesome natural pet food. We'll build on this momentum in calendar 2021 by launching innovation into segments of the category where the blue brand is less developed, including wet cat food and pet treats.
For example, wet cat food is roughly a $5,000,000,000 product segment in the U. S. With wholesome natural products only representing about 15% of segment sales with significant opportunity for expansion. Blue will lead the naturalization of the wet cat food segment with the introduction of our new tastefuls line, which launches next month. We've combined our deep category expertise and our technical know how to develop a line of tasteful products that delivers on our true blue promise with only the finest natural ingredients while satisfying cats more demanding palates.
Our message to pet parents is simple. One taste is all it takes for your cat to realize how delicious this product is and for pet parents to realize that taste and healthy ingredients don't have to be mutually exclusive. We'll support this launch with dedicated investment leveraging our Blue integrated marketing model. We're excited about this next step as we continue to expand the Blue brand across the pet food category and we'll have more innovation to share as we move through calendar 2021. The 3rd way we're winning is by leveraging our scale with advantaged capabilities.
Specifically, we believe data and analytics will provide the foundation to drive differential growth and efficiency for our enterprise, acting as an enabler for strategic capabilities such as SRM, e commerce, digital marketing, integrated planning and Let me share an example of how data and analytics is uncovering exciting growth opportunities in digital marketing. Data driven digital marketing is beginning to fuel every aspect of the General Mills brand experience from strategy through conversion in a holistic connected approach. We're getting smarter every day about how we collect and connect data to gain better insights about consumers and where to play, as well as how to continuously optimize how we activate our messages. The process for unlocking growth starts with data. We're building rich data sets, including first party data captured through our proprietary platforms such as Box Tops for Education and our bettycrocker.com and pillsbury.com websites, which interact with 8,000,000 unique users each month.
Next, we connect those data sets and use our advanced analytics capabilities to identify previously untapped growth spaces. From there, we segment consumers and rapidly test multiple iterations of personalized marketing messages. And with the direct link between our digital marketing and e commerce purchases, we can quickly measure sales impact and assess effectiveness. This agile marketing process is providing end market learning 4 to 6 times faster than our normal process. Finally, we scale the learnings and automate the process to efficiently drive growth.
A great example of how we're applying this today is our ratio brand, which is geared for consumers seeking keto friendly food options. We connected multiple data sets and created over 200 versions of marketing messages, more than 25% of which directly connected to an e commerce site. From our analysis, we learned who our top growth audience is and the content that resonates most for them. We strove a 24% increase in sales per point of distribution when we scaled up the media. In another example, we're leveraging connected data and rapidly iterating on marketing messages that reinforce the great value that brands like Pillsbury can offer during this economically challenged time.
Through this process, we identified optimal consumer segments, messaging timing and media placement resulting in double digit sales lifts. Though it's early, we're encouraged by the results we've seen across these personalized marketing implementations. We'll continue to invest and build this capability to drive speed in our learning and decision making to enable future growth. I'll now pass it over to Kofi to share more details of our Q2 financial results.
Thanks, Jeff, and hello, everyone. Let's start with our Q2 financial results on Slide 16. Net sales of $4,700,000,000 were up 7%. Organic net sales also grew 7% in the quarter as we continued to compete effectively amid the elevated consumer demand driven by the pandemic. Adjusted operating profit of 866 $1,000,000 increased 6% in constant currency, primarily driven by higher net sales, including positive price mix.
This was partially offset by higher input costs, including costs to secure incremental capacity. The comparison to the prior year quarter that included favorable manufacturing leverage and higher SG and A expenses, including a double digit increase in media investment. Adjusted diluted earnings per share totaled $1.06 in the quarter and grew 9% in constant currency, primarily driven by higher adjusted operating profit, lower net interest expense and higher after tax earnings from joint ventures. Slide 17 summarizes the components of our net sales growth in the quarter. Organic net sales were up 7% with 4% growth in organic pound volume and 3 points of positive organic price mix.
Now let's turn to segment results beginning with North America Retail on Slide 18. 2nd quarter organic net sales were up 9%, led by 18% growth in U. S. Meals and Baking, 6% constant currency growth in Canada and 4% growth in U. S.
Cereal. 2nd quarter Nielsen measured U. Capacity and consumer demand come into better balance. We continue to compete effectively in NAR, including year to date market share gains in both the U. S.
And Canada. The strength of our brand building, supply chain and sales execution enabled us to hold or gain share in 8 of our top 10 U. S. Categories through the first half of this fiscal year. 2nd quarter constant currency segment operating profit increased 9%, driven by volume growth and fixed cost leverage in supply chain, partially offset by higher operational cost to service demand, the comparison to the prior year period that included a timing related manufacturing benefit and higher SG and A expenses, including a double digit increase in media investment.
As Jeff mentioned, our organic net sales for our Pet segment grew 18% in the 2nd quarter, driven by broad based growth across all product segments, including double digit growth for both dog food and cat food, more than 25% growth for wet food and roughly 40% growth for treats. The 18 percent organic net sales growth was driven by all channel retail sales that were estimated to be up double digits and an estimated mid single digit benefit from increased retail inventory. This quarter's top line performance is on top of mid teens organic net sales growth a year ago, when our results benefited from Blue's most recent significant distribution expansion. Through the first half of the year, Blue has continued to gain share and grow household penetration as we drive awareness and benefit from Blue being available almost everywhere pet parents shop. Net sales were up 13% in the first half and we estimate roughly 2 points of that growth represented increased retail inventory.
On the bottom line, Pet's 2nd quarter segment operating profit grew 48% in constant currency, driven by strong volume growth, positive price mix and benefits from cost savings, partially offset by higher media 14% in the quarter, driven by the continued reduction in away from home demand amid the pandemic. We continued to see double digit declines in consumer traffic negatively impact the segment's key away from home channels, including restaurants, schools, lodging and convenience stores. While the away from home industry is seeing headwinds, competing well and we've gained market share in measured channels through the first half of fiscal twenty twenty one. Segment operating profit in the quarter was down 32%, driven by lower net sales and fixed cost deleverage in supply chain. In Europe and Australia, 2nd quarter organic net sales increased 3%, primarily driven by growth in Old El Paso Mexican Food and Haagen Dazs Retail Ice Cream.
We've competed effectively year to date, holding or growing market share in France and the UK, the segment's 2 largest markets and growing share in Mexican food and snack bars. 2nd quarter segment operating profit increased 7% in constant currency, driven by higher net sales, including positive price mix, partially offset by higher media investment and higher input costs. In Asia and Latin America, 2nd quarter organic net sales grew 10%. Net sales were up double digits in Latin America, driven by continued strong growth of Yolky Meals and Snacks and Catano Seasonings in Brazil. Net sales were up high single digits in Asia in the quarter, driven primarily by Wanchai Ferry Dumplings in China and by Haagen Dazs Retail Ice Cream.
This was partially offset by continued declines in away from home food service outlets and Haagen Dazs shops. 2nd quarter segment operating profit increased 8% in constant currency, driven by higher net sales, partially offset by higher media and other SG and A expenses and higher input costs. Slide 23 summarizes our joint venture results in the Q2. Cereal Partners Worldwide posted another strong quarter of top line growth with constant currency net sales up 7%. CPW's net sales growth was broad based led by Latin America, Russia, Turkey and Australia.
Haagen Dazs Japan net sales were up 12% in constant currency, including innovation driven volume growth and positive price mix in the quarter. 2nd quarter combined after tax earnings from joint ventures increased 46% to $36,000,000 primarily reflecting the strong net sales growth at both CPW and Haagen Dazs Japan. Turning to total company margin results. 2nd quarter adjusted gross margin increased 20 basis points, primarily driven by positive price mix, partially offset by higher input costs, including the cost to secure incremental capacity and the comparison to the prior year period that included favorable manufacturing leverage. Adjusted operating profit margin in the quarter decreased 10 basis points, driven by higher SG and A expenses, including a double digit increase in media spending, partially offset by the adjusted gross margin expansion I just mentioned.
The 2nd quarter adjusted operating profit margin result was somewhat ahead of our expectations for two reasons. 1st, we were able to service more demand from our internal capacity than we initially expected. And second, we saw some of our external manufacturing needs and other operational costs shift into the second half. Slide 25 summarizes other noteworthy Q2 income statement items. Unallocated corporate expenses, including certain items affecting comparability increased $19,000,000 in the quarter.
Net interest expense decreased $19,000,000 from a year ago, driven by lower average debt levels. The adjusted effective tax rate for the quarter was 22.3% compared to 21.9% a year ago, primarily driven by non recurring discrete benefits in fiscal 2020, partially offset by favorable earnings mix by market in fiscal 2021. And average diluted shares outstanding were up 1%. Our fiscal 2021 first half results are summarized on Slide 26. Net sales of $9,000,000,000 were up 8%.
Organic net sales were also percent, including growth from organic volume and positive organic price mix. Year to date, adjusted operating profit of $1,700,000,000 increased 13% in constant currency, primarily driven by higher net sales, partially offset by higher input costs and higher SG and A expenses, including a double digit increase in media investment. Adjusted diluted earnings per share totaled $2.06 in the first half and grew 17% in constant currency, driven by higher adjusted operating profit, higher after tax earnings from joint ventures and lower net interest expense, partially offset by higher diluted shares outstanding and a higher adjusted effective tax rate. Turning to the balance sheet and cash flow. First half operating cash flow totaled $1,400,000,000 down 2% from the first half of last year, primarily driven by changes in inventory and the timing of accounts payable.
Our core working capital decreased $331,000,000 from a year ago, primarily driven by improvements in accounts payable. Capital investments through 6 months of $226,000,000 increased $68,000,000 from a year ago, including higher spending on growth capital. And we paid $618,000,000 in dividends in the first half. Turning to our expectations for the balance of fiscal 2021. We've outlined some key assumptions on Slide 28.
We expect the pandemic will drive continued elevated consumer demand for food at home relative to pre pandemic levels through the remainder of fiscal year. We expect 3rd quarter demand trends to be generally consistent with recent months due to the ongoing virus concerns in many markets around the world. And we expect to continue to invest in our brands and capabilities to generate profitable growth over the long term and throughout the pandemic. Based on these assumptions, we expect to generate continued strong top and bottom line growth in the 3rd quarter with organic net sales growth roughly similar to the 2nd quarter's growth rate and an adjusted operating profit margin in line with the prior year. As we look further out, we expect 4th quarter net sales to be above pre pandemic levels, though below Q4 of fiscal 2020 due to the difficult comparison in the year ago period, when net sales grew 21% behind the initial pandemic driven surge in at home demand, the 53rd week and the extra month of results in our Pet segment.
Finally, due to first half adjusted operating margin results that were somewhat ahead of our expectations, we now anticipate our full year fiscal 2021 adjusted operating profit margin will be in line or better than last year. Let me now turn it back to Jeff for some closing remarks.
Thanks, Kofi. I'll close with a few thoughts. I'm proud of how the entire General Mills team continues to execute and deliver strong performance amid a challenging and dynamic environment. We're focused on what we can control, meeting our consumers' needs and winning across our markets. I am confident that we're taking the right actions to ensure we continue to win both today and for the long term.
I want to thank you for your time this morning. This concludes our prepared remarks. I invite you to listen to our live question and answer webcast, which will begin at 8 am Central Time this morning