In case you haven't come across these yet, here are a couple of potentially helpful reports from the FHWA released in 2016:

Bicycle-Pedestrian Count Technology Pilot Project which compares different types of counters and lessons learned

Guidebook for Developing Pedestrian & Bicycle Performance Measures including a toolbox for different contexts (see Chapter 4)

(additional resources to Guidebook above including webinar recording and slides)

cheers,

Beth

--