Have a look at the graphs in https://en.wikipedia.org/wiki/Demography_of_the_Netherlands and notice how the growth percentage has only just reached 0%, despite fertility rate having plunged all the way to near 1.5 since the 1970s. What's more, many still predict population growths and the government is still stimulating it through subsidizing children and giving tax breaks to immigrants. The Netherlands is on the cusp of declining, but not declining yet.

If you look up the history of fertility rates, most of developed Europe plunged similarly, yet population kept growing well up to now.