the area I am at the # of witnesses appears to be shrinking.
Same here.
When I was a kid (lived in the same area) there would be a congregation splitting every couple years, and constant complaints about how full the KHs where (in some cases there would be 7 congregations to a double auditorium KH while they waited for a new one to be built). There was apparently huge growth in the area all through the 90s and early 2000s. A lot of the growth was just due to the growth of the city in general, but there where probably 3-6 baptized in my congregation at every convention and 1-2 for every assembly. Now, I can't remember the last time we've had a congregation split. The KH that used to never have less than 6 congregations in it now has 4. There hasn't been anyone baptized in our congregation in years, and the last assembly with over 1000 in attendence saw 3 born-ins baptized.
They may be growing, but it's not here, and if they're growing in any developed coutries, it's not by more than 1% annually and poised to start declining.