is node tool row count always way off?

[Hiller, Dean]

The node tool cfstats, what is the row count estimate usually off by(what 
percentage? Or what absolute number?)

We have a CF with 4 rows that prints this out….

                Column Family: bacnet11700AnalogInput8
                SSTable count: 3
                Space used (live): 13526
                Space used (total): 13526
                Number of Keys (estimate): 384

An SSTable of 3 sounds very weird….do I need to compact it myself….it's been 
like this for around 12 hours.

Thanks,
Dean