Well as a non-techie guy, I could use a graph
For non-techies, there is easily accesible and avalaible information (including a short tutorial) at:
https://www.thorlabs.de/newgrouppage9.cfm?objectgroup_id=285
13A/W at 850 um is off-the typical chart below, indeed 20 times the typical best in-class responsitivity of inGaP-GaAs of 0.65 (0.65 x 20 = 13)