Rent Increase Question

[Teawanda Wells]

What is the typical annual increase in rent? I have a single family house that has no mortgage. I've been renting to the same family (elderly couple and their adult daughter) for the last 3 years with no increase. Why no increase...rent has been paid on time every month with exception of two times within the 3 years and I guess I'm nice :). Lease is to be renewed in the next 2 months and I am definitely increasing rent this year due to increasing property taxes and insurance. Just curious as to the typical annual increases.