5.6 million buildings in the U.S.,https://css.umich.edu/factsheets/commercial-buildings-factsheet In the Dec 15,video Paul G said " What we say to potential commercial customers, if you think of the cost of a vacant office, what is the cost per day if it is vacant, the cost of Biocloud is pale in comparizon to the cost of not getting any rent (revenues)".
5.6 million buildings X the number of floors(scary number)... and that is just for the USA.