Complete dataset of NYC building units

I am looking for a dataset that shows the number of units in each NYC building. The most complete dataset on NYC buildings that I’ve come across so far is the PLUTO dataset, which is referenced by Kaggle as being:

a master record of the locations and characteristics of buildings in New York City.

However, the latest version of this dataset has 858k rows and according to other sources, there are > 1 million buildings in NYC.

Does anyone know why some buildings are excluded and if there is a more complete dataset to analyze the number of units in buildings?