If you truly have population data, then inferential statistics will not help you, as the aim of the tool is to aid in making inferences in the presence of sampling error--to reason from a finite set of observation to an infinite population.
Populations are not always infinite. Finite population corrections are available (or can be constructed) to adjust for the sampling variance reduction that occurs when sample size becomes an appreciable fraction (say, 5%) of population size. Sampling variance approaches zero asymptotically as sample size approaches population size.
In disciplines where finite population corrections have not taken hold (or are seen as "hard to do"), it is common to shortcircuit concerns about the matter by imagining some infinite population, even when there is good evidence that the entire population has been counted. One might imagine that respondents are actually typical of some larger set of respondents. But as the late gadfly David Freedman once wrote, "Generalizations to imaginary populations are themselves imaginary."