This article examines (the frequency of) the progressive passive construction (e.g. is being taken) in Present-day English. Through the examination of the large-scale corpora such as COCA, COHA, BNC, we found out that the frequency of this construction is very low. In particular, the frequency of the complex construction, containing more than three auxiliaries like may be being taken / has been being taken / may have been being taken, is much lower. Thus we need to answer why the frequency is so low. We propose a formula predicting the frequency of the complex construction like ([Frequency of the Complex A-B Construction] ≤ ([Frequency of the A Construction] × [Frequency of the B Construction]). According to this formula, the frequency of the progressive passive is directly related to the frequency of the progressive and that of the passive. The progressive is increasing these days, but the passive is rapidly decreasing, especially in AmE. This fact is reflected in the decrease of the progressive passive construction. Another (minor) reason of the low frequency is that some other rival constructions, e.g. the passival and the get-passive, are used, along with the progressive passive.