LTC6990 - fout accuracy

Hello,

I'm using this component in the recommended range of Rset.

According to the datasheet, the frequency accuracy in this case is up to 2.2%.

I'd like to know the meaning of this accuracy - is it a single period accuracy or an average accuracy?

i.e. if I measure the output frequncy for many cycles, should it give have a better accuracy than 2.2% or it means that the average frequency will be with an a accuracy of 2.2%?

Thanks