I have a circa 1993 Icom GP-22 GPS device.
The instruction manual says that it takes 10 minutes to collect the almanac, and that once the almanac is stored, then subsequent position calculations take from 1 to 3 minutes.
1993 - 10 minutes to collect the almanac, and 1 to 3 minutes to calculate the position.In my experience in using the device, the 10 minutes to collect the almanac is about right, give or take a minute or two. The 1 to 3 minutes to calculate the position was also correct, with the caveat that usually the time was closer to 3 minutes than 1 minute.