WPO Stats is a super-useful collection of stats from Tammy Everts and Tim Kadlec to demonstrate the business value of faster websites. If you need support for making the business case for your performance project, here’s your go-to library.
A sampling:
BBC has seen that they lose an additional 10% of users for every additional second it takes for their site to load. [source]
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AliExpress reduced load time by 36% and saw a 10.5% increase in orders and a 27% increase in conversion for new customers. [source]
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For every 100ms decrease in homepage load speed, Mobify’s customer base saw a 1.11% lift in session based conversion, amounting to an average annual revenue increase of $376,789. [source]