Averaging it out is going to be weird, because most comics on Tapas over 500 subs got them in bursts during features, not in ongoing streams. It's maybe not a good way to compare yourself to others, because...er... well, let me do the maths here:
Errant has been running just over three years, so 1,100 days... Has 2359 subs and 26,000 likes, so....
Subs per day: 2.1
Likes per day: 23.6
Likes are particularly wonky because the more pages/episodes you have, the more likes you're likely to have. I have well over a hundred pages at this point. 
It'd be more accurate to say that an average update now hits about 100 likes by the end of the week (obviously was not the case early on), but also sometimes I get "like bombers" reading through and liking all the pages as they read, which creates spikes and skews the number.
The subs are a bit wonky, like in a typical week, assuming I'm not featured, I'm more likely to get about 3-10 subs in the week. But when featured, depending on the type and placement of the feature, I've had anywhere from 50-250 new subs in the space of three days to a week. The first time I got a Staff Pick, I had 275 or so subs, and got 250 new ones, almost doubling the total number!
To people comparing yourselves to others, don't forget that performance varies by medium (comics tend to have bigger numbers than novels), and by genre (if you're sci-fi, compare your performance with other sci-fi. The readership is one of the smallest on the site, so comparing yourself to BL, which has the biggest audience on the site, is going to give you a totally skewed perception of how you're doing).
