Bug: Incomplete charts when values are zero

[vevetron]

Describe the bug
Sometimes at the left and right of a chart data is missing. Or in the middle when there are zeroes the chart gives a straight line instead of hitting zero first.
https://reports.calitp.org/gtfs_schedule/2024/08/273/

I'm having trouble finding cases that aren't Sacramento though. For Sacramento there is a gap in GTFS coverage when they are between GTFS files since they publish theirs early.

Expected behavior
We should see it drop to zero.

[vevetron]

https://reports.calitp.org/gtfs_schedule/2024/08/243/ - there is a gap here.