If you are happy with your mileage crack on!
Personally, I don't tend to take note of mileage so much these days and prefer to think in terms of time on the bike (I had to go look up my data to see what 100 miles equates to in time for me). How long do you spend riding your bike? Does it impact on other things in your life? Do you enjoy it? All more important questions IMO.
How long do you spend riding your bike? - I'm not that fast but don't push 100%. I hold the same average over 100km as I do for 10km... on the road bike it is about 12-13mph in the winter months, so I guess about 7-8hrs a week average. I cycle in all weathers. Time wise mycyclinglog tells me I have done 104hrs so far this year in all weather, but that is around 2200km and covers my mountain biking as well as my road bike & touring bike.
Does it impact on other things in your life? What life? I don't have a job, no longer live close to where we used to before we went off to cycle around the world, and tis my only transport. I also live rurally. I do feel like I stripping

... pj's, normal, lycra, normal, pjs... otherwise the cycling allows me to get from A-B (college twice a week so 30 miles total) physio once a week (that's a 25 mile round trip), plus a once a fortnight visit to my parent's (45 mile round trip) or my grandfather's once a month, (65mile round trip), tomorrow.
I do also go out recreationally as well both solo and with my husband as and when he is home.
Do you enjoy it? Yes - the weather does not bother me and rather like mountaineering in the rain, I rather enjoy cycling in the rain and despite the sunshine, today is the first time I have been out this week!