The Masked Marvel writes:

SR44 (or S76, EPX76, PX76, MS76, V76PX, 357) is silver oxide,
LR44 (or A76) is alkaline, the latter's cheaper and shorter lived.

The problem is discharge characteristics, not lifetime. This mimics short
lifetime in devices that are sensitive to voltage droop, like calipers, but
that's not really the problem. Most of the mA-hours remain in an alkaline
cell when it quits working in calipers.

See my Web page cited earlier for details.