Ah interesting. For reference the two-month earlier version is at
https://metrolinx.files.wordpress.com/2019/01/click-right-here-for-our-ridership-map.pdf
I'm not sure what the green ridership change is being compared to. It's not to November 2018. For example St. Catherines decreased from 18 riders a day to 14 riders a day, but the "ridership change" increased from 5.4% to 5.9%.
West Harbour reduced from 58 riders a day to 57 riders a day, but the "ridership change" decreased from 6.3% to 5.2%.
I'm not even sure what the "average daily" is measuring. Normally it's a typical week day. But every line is down from November, and Union is down from 75.2K to 73K. It's almost like they divided by total days, including holidays (Christmas week!) etc. ... which would be very unusual!
The only thing I see that bucks the trend is Downsview Park, which increased 280 to 285 riders a day! So that's positive.