The purpose of the capacity panel in Remix Streets is to aid in discussions and bring the focus back to people movement. As NACTO states, "biking and high-capacity transit must remain a key component of streets, with dedicated space, in order to move the largest numbers of people who live in growing cities".
The capacity ballpark estimates come from NACTO's Blueprint for Autonomous Urbanism Fall 2017 as well as NACTO's Complete Street Design Guide. See page 50 of the Blueprint shown here.
Based on NACTO's free-flow people capacity for bikeways, bus and rail lanes, and private vehicle lanes shown above, we used a conservative estimate for each range, assuming the following:
Private vehicle ("drive") lane: 1,600 people / hour
Bicycle lane: 1,000 people / hour
Bus or rail lane: 6,000 people / hour
The sidewalk capacity follows the Highway Capacity Manual (HCM) formulas and adjusts depending on the effective sidewalk width. In addition, if a street segment is split into two or more, Remix will choose to display the lowest capacity total along the segment since the segment's capacity is limited or constrained by a pinch point cross section. This particular feature can be easily turned on or off by the user and at this time, the user cannot input their own capacity numbers but please give us that feedback so we can improve.