Hello, I don't know English, so please forgive me for using a translator. In this topic, I was able to determine the production level of the MiG-25 with a high degree of certainty.
By 1978, a total of 518 pre-series and serial MiG-25P aircraft were produced at Plant No. 21: 2 in 1966, 5 in 1967, 10 in 1968, 20 in 1969, 20 in 1970, 40 in 1971, 30 in 1972, 25 in 1973, 40 in 1974, 50 in 1975, and 276 between 1976 and 1978.
From 1978 to 1984, 104 MiG-25PDs were built, including, as already mentioned, 38 for export.
Between 1979 and 1984, approximately 370 MiG-25Ps were converted to the MiG-25PDS standard.
Between 1969-72, a total of 23 reconnaissance aircraft were produced MiG-25R, 10 in 1969, 5 in 1970, 6 in 1971 and 2 in 1972r.
Between 1972 and 1982, it produced 196 MiG-25RB, RBW, RBK, and RBS aircraft, 15 in 1972, 25 in 1973, 35 in 1974, 15 in 1975, and 106 between 1976-82.
Between 1969 and 1982, a total of 173 MiG-25PU trainers were produced.
Between 1972 and 1982, Plant No. 21 in Gorki produced a total of 48 MiG-25RU trainers.
In total, between 1966 and 1985, Plant No. 21 built 1,106 aircraft of this series. MiG-25 (Foxbat), for the USSR Air Force and for export, of which 622 were fighters, 223 reconnaissance-bombers, 221 trainers, and 40 ground-attack/anti-radar aircraft.
The above data seems to confirm that in 1990 the USSR had no more than 430 MiG-25P/PU fighters, 175 MiG-25R/RU reconnaissance aircraft, and 40 MiG-25BM strike aircraft in service.
I'm sorry again that I'm messing up the translation