Thank you for joining today's call. I'd like to start with a few comments on what we're seeing as we're coming out of the pandemic, both on the customer experience side and on the operating cost side in this current inflationary environment.
Let's start with demand and customer experience. Worldwide net sales in Q1 were $116.4 billion, an increase of 9% year-over-year, excluding the impact of foreign exchange. This is the top end of our guidance range of $112 billion to $117 billion.
Our compound annual growth since before the pandemic stands at 25%, a growth rate higher than what we were seeing before the pandemic. Our prime members continue to be a key driver of growth. Prime members have meaningfully increased their spend since the start of the pandemic, and we continue to see consistently high member renewal rates. We also added millions more new Prime members during the quarter. Throughout the past two years, we've seen stronger usage of Prime benefits by Prime members and a greater reliance on Amazon for their shopping and entertainment. In the first quarter, we made encouraging progress on key customer metrics.
Delivery speed performance is now approaching levels not seen since the months immediately preceding the pandemic in early 2020. And we now have the widest selection ever available for Prime's fast delivery. We have worked to protect and enhance the customer experience despite a sharp increase in costs, particularly over the past three quarters. We've seen a large cost to keep up with demand these past two years. During this period, we doubled the size of our operations and nearly doubled our workforce to 1.6 million employees. Labor and physical space are no longer the bottlenecks they were throughout much of 2020 and 2021. However, we continue to face a variety of cost pressures in our consumer business. We'll break these into two buckets, externally driven costs, primarily inflation; and internally controllable costs, primarily productivity and fixed cost deleverage. The externally driven costs are a result of intensifying inflationary pressures throughout Q1.
Line haul air and ocean shipping rates continue to be at or above the rates in the second half of last year, which were already much higher than pre-COVID levels. Some of this is due to the impact of the Omicron variant in China and labor shortages at point of origin, and the start of the war in the Ukraine has contributed to high fuel prices. For example, the cost to ship in overseas containers more than doubled compared to pre-pandemic rates. And the cost of fuel is approximately 1.5 times higher than it was even a year ago. Combined with the year-over-year increases in wage inflation, these inflationary pressures have added approximately $2 billion of incremental costs when compared to last year. While we will continue to look for ways to mitigate these costs, we expect they will be around for some time. The next bucket of costs related to productivity and fixed cost leverage, which we consider to be more within our control and are working to reduce. These additional costs correspond to the state of the labor force and fulfillment network following two years of disruption and large demand variability. We now look forward to more predictability in our consumer order patterns and greater stability in our operations.
Let's start with labor. As a reminder, in the second half of 2021, we were operating in a labor-constrained environment. With the emergence of the Omicron variant in late 2021, we saw a substantial increase in fulfillment network employees that on leave, and we continue to hire new employees to cover these absences. As the variant subsided in the second half of the quarter and employees returned from leave, we quickly transitioned from being understaffed to being overstaffed, resulting in lower productivity. This lower productivity added approximately $2 billion in costs compared to last year. In the last few weeks of the quarter and into April, we've seen productivity improvements across the network, and we expect to reduce these cost headwinds in Q2. The last issue relates to our fixed cost leverage.
Despite still seeing strong customer demand and expansion of our FBA business, we currently have excess capacity in our fulfillment and transportation network. Capacity decisions are made years in advance, and we made conscious decisions in 2020 and early 2021 to not let space be a constraint on our business. During the pandemic, we were facing not only unprecedented demand, but also extended lead times on new capacity. And we built towards the high end of a very volatile demand outlook. Now that demand patterns have stabilized, we see an opportunity to better match our capacity to demand.
We have lowered our operations, capital expenditures for 2022 and are evaluating other ways to increase our fixed cost leverage. We estimate that this overcapacity, coupled with the extraordinary leverage we saw in Q1 of last year, resulted in $2 billion of additional costs year-over-year in Q1. We do expect the effects of these fixed cost leverage to persist for the next several quarters as we grow into this capacity. When you combine the impacts of the externally driven costs and the internally controllable costs, you get approximately $6 billion in incremental costs for the quarter. Approximately two-thirds of these costs are within our control. And with demand normalizing, we remain focused on rightsizing our cost structure and driving out any cost inefficiencies. Our guidance includes an expectation that we will incur approximately $4 billion of these incremental costs in Q2. We saw another strong quarter of innovation and customer engagement in the AWS segment, where net sales were $18.4 billion in Q1, up 37% year-over-year and now represent an annualized sales run rate of nearly $74 billion.
Developers at organizations of all sizes from governments and not-for-profits to start-ups and enterprises continue to choose Amazon Web Services. Companies like Telefonica, Verizon, Boeing, MongoDB, Amdocs, Bundesliga, Maple Leaf Sports & Entertainment, the NHL and Thread announced new agreements and service launches supported by AWS. We also continue to build support infrastructure to best serve AWS' millions of customers. We recently completed the launch of our first 16 local zones in the United States with 32 more to come across 26 countries. Local zones extend AWS regions to place our services at the edge of the cloud near large population, industry and IT centers, expanding our infrastructure footprint and enabling customers to build with single-digit millisecond latency performance. Last quarter, I provided some detail on our overall capital investments. So, let me add to that with our current thinking. First, as a reminder, we look at the combination of CapEx plus finance leases. Capital investments were $61 billion on the trailing 12-month period ended March 31. About 40% of that went to infrastructure, primarily supporting AWS, but also supporting our sizable consumer business. About 30% is fulfillment capacity, primarily fulfillment center warehouses. A little less than 25% is for transportation. So, think of that as the middle and last-mile capacity related to customer shipments.
The remaining 5% or so is comprised of things like corporate space and physical stores. For full year 2022, we do expect infrastructure spend to grow year-over-year, in large part, to support the rapid growth in innovation we're seeing within AWS. We expect infrastructure should represent about half of our total capital investments in 2022.
For the consumer business, as I said earlier, we currently have some excess capacity in the network that we need to grow into. So, we've brought down our build expectations. Note again that many of the build decisions were made 18 to 24 months ago, so there are limitations on what we can adjust midyear.
That said, we expect fulfillment dollars spent on capital projects to be lower in 2022 versus the prior year. We also expect transportation dollars spent on capital projects to be flat to slightly down. Finally, I'll highlight a few additional items.
We reported an overall net loss of $3.8 billion in the first quarter. While we primarily focus our comments on operating income, I'd point out that this net loss includes a pretax valuation loss of $7.6 billion, included in nonoperating expense from our common stock investment in Rivian Automotive. You may remember that we had a $12 billion gain on Rivian in Q4. We also provided our second quarter financial guidance as part of our earnings release.
As a reminder, our comparable period of Q2 2021 included the continuation of extraordinary net sales growth in roughly the first half of that quarter. That began to moderate in the second half as vaccines became more readily available in many countries and people started getting out of their homes. In addition, note that this year's Prime Day sales event will occur in the third quarter, in July to be specific. Last year, in 2021, Prime Day occurred in the second quarter. Prime Day contributed about 400 basis points to our Q2 2021 year-over-year revenue growth rate.
Lastly, as you look at our Q2 operating income guidance, a reminder that we will see our seasonal step-up in stock-based compensation expense as our employees receive annual restricted stock unit grants in the second quarter. This year, we expect to see stock-based compensation expense of approximately $6 billion, up from $3.3 billion in Q1, largely reflecting wage inflation as we continue to hire and retain employees in high-demand areas, including engineers and other tech workers. With that, let's move on to your questions.