A requirement on a software project is it should run on typical business laptops up to X years old. However while given a specific model number I can normally find out when it was sold, I can't find data to do the reverse... for a given year I want to see what model numbers were released/discontinued.

We're talking big-name, popular models like Dell Latitude/Precision/Vostro, Thinkpads, HP, etc. The data for any model is out there but getting a timeline is proving hard. Sites like Dell are (unsurprisingly) geared around current products, and even Wikipedia isn't proving very reliable.

You'd think this data must have been collated by manufacturers or enthusiasts, surely?