Michael Mullican
Analyst · JPMorgan
Thanks, Ken. Good morning, everyone. The first quarter exceeded our expectations as the demand we saw throughout 2020 continued and, in fact, accelerated into 2021. First, I want to highlight our record first quarter results, then I will discuss our 2021 guidance, which we are increasing based on the continued strength of our business.
As Ken mentioned, first quarter net sales were $1.58 billion with comparable sales of 38.9% despite firearms and ammo sales being lower than expected due to continued inventory challenges. When compared to Q1 2019, sales increased 46.8%.
Sales were strong across all product categories as well as across all markets. This is the second quarter in a row that all 4 merchandise divisions had double-digit comparable sales growth.
Our e-commerce sales declined 21% over last year as we anniversary 405% growth in Q1 of 2020 when the COVID crisis began and customers shifted their buying preferences to digital channels. When measured against Q1 2019, our e-comm sales grew 300%, and the sales penetration rate increased to 7.4% versus 2.8%. Because buy online, pick up in store remains approximately 50% of total e-commerce sales, which reduces our overhead and shipping costs, we have been able to grow our e-commerce sales and our profitability. In fact, since 2019, the company's pretax income has increased 767% even as our Q1 e-comm sales have grown 300%, highlighting the fact that we have a profitable omnichannel platform.
We believe there is even more room for growth and improvement as we continue to increase our investment in academy.com to create a seamless omnichannel experience. We are implementing solutions to improve our search and checkout capabilities to give our customers more personalized product recommendations and to provide them with more payment options like Apple Pay.
During the first quarter, gross margin dollars increased 89% to an all-time Academy Sports + Outdoors record of $563.7 million. The margin rate expanded by 950 basis points to 35.7% driven by a more favorable merchandise mix, better pricing management, fewer promotions and less clearance sales. SG&A expenses were $324.6 million or 20.5% of sales, which was 450 basis points less than Q1 2020 and 750 basis points lower than Q1 2019. These record results led to pretax income of $224.9 million compared to a loss of $9.5 million in Q1 2020.
The first quarter tax rate was 21%, resulting in net income of $177.8 million.
Pro forma adjusted net income, which excludes the impact of certain extraordinary items, was $182.5 million compared to $440,000 in Q1 2020. Q1 diluted earnings per share were $1.84 per share compared to a loss of $0.14 per share in Q1 2020. Pro forma diluted earnings per share were $1.89 per share compared to $0.01 in Q1 2020.
Moving to the balance sheet. We ended the quarter with $593.3 million in cash and 0 borrowings on our credit facility. We have reduced our net debt by 84% compared to last year, a decrease of over $1 billion. At the same time, we have increased our liquidity including availability under our credit facility by 42%, which is an increase of over $400 million. During Q1, the company generated $219.2 million in operating cash flow compared to $90.8 million in Q1 2020.
Ending inventory was $1.08 billion, which was 7% higher than Q1 2020 and 9% higher than at the end of Q4 2020. Steve will provide more insight on how his team has effectively managed tighter product availability while driving tremendous sales growth.
As far as capital expenditures, the company still expects to spend $80 million to $85 million in fiscal 2021.
On the last earnings call, I laid out 4 sales-driving opportunities for 2021. Those opportunities were: first, capitalizing on the shopping velocity of new and existing customers; second, ensuring that we are replenishing and growing categories where inventory was constrained through most of 2020; third, capitalizing on several product categories that were challenged in 2020 but are positioned to benefit from the reopening of the economy; and lastly, improving our management of several seasonal categories where demand exceeded supply in 2020.
Here are some indicators of how we are doing so far. We continue to see an increase in the percentage of existing customers who purchased in a new category in the last 12 months and then returned to that category again. Our inventory levels in categories that saw shortages in 2020, like bikes and fitness equipment, ended in a much better position than a year ago. Team sports, apparel and footwear all had record sales growth well above the company's total comparable sales after being challenged in Q1 2020. Sales in categories where we didn't have enough supply last year, like water sports and outdoor cooking exceeded our Q1 comp.
Moving to our outlook for the remainder of 2021. We are increasing our full year sales and earnings guidance. While there is still uncertainty from the impact of COVID-19 and other external factors based on recent trends and the visibility we have for the remainder of 2021, full year comparable sales are now forecast to range from plus 6% to plus 9%. Over the last 2 fiscal years, this would represent comp growth of 22% to 25%.
Diluted earnings per share are now forecast to range from $4.15 per share to $4.50 per share based on 96.5 million diluted weighted average shares outstanding for the full year. This range accounts for various market scenarios and possible outcomes for the remainder of the year, bearing from business as it is today to a much more promotional and competitive environment.
In terms of year-over-year growth, net income at the midpoint of this guidance and earnings per share using a normalized share count of 96 million shares are both 35% higher than fiscal 2020 and 248% higher than fiscal 2019.
With that, I will turn the call over to Steve for more details around merchandising operations. Steve?