I've been unclear about this for a while and a recent question on this site prompted me to ask for clarification.
Consider the sentence, 犯罪が増えている. In this sentence, is it implied that the increasing has stopped? In other words, does 増える represent an instantaneous state change between some smaller amount and some larger amount or does it represent a process that can continue?
If 増えている represents a progressive process and this implies that the increasing in continuing, is it grammatical to include an amount? Is 「三倍増えている」acceptable and if so, what does it mean given that the increasing changing?
If it is ambiguous, how could it be clarified?