Binod-ji,
Here are the number of Rafi songs 'released' from the year 1975 onwards. The Source is Geet Kosh and (as you mentioned) Surjit Singh:
Rafi (1975-1980)
1975: 68
1976: 67
1977: 101
1978: 91
1979: 84
1980: 265The figures for 1980 also include Rafi songs
released in the years after 1980 which were recorded before July 31st 1980. As per these figures, once Rafi's total jumps in 1977, it stays consistent for about two years before jumping in a huge way in the last year of his life. The songs released in 1980 could have been recorded prior to that year (i.e 1979) and the same can be said about previous years before that. Now let us compare these stats with the years 1970-1974:
Rafi (1970-1974)
1970: 131
1971: 131
1972: 95
1973: 80
1974: 83Now here is something interesting. Now let me post the Kishore stats for comparison purposes:
Kishore (1970-1980)
1970: 47
1971: 102
1972: 137
1973: 146
1974: 137
1975: 106
1976: 103
1977: 147
1978: 122
1979: 77
1980: 126Now take a look at the stats when comparing Rafi and Kishore in terms of Total Output. Even after Aradhana (I always maintain this film didn't do anything to Rafi, but only raised Kishore's popularity), Rafi still had more released songs than Kishore in 1970 and 1971. Come 1972, Kishore's total is more and he maintains this until 1979 where Rafi regains numero uno in Total output (ofcourse by 77 he was already commercially back on top with Kishore). The rest of the stats show that Kishore's output year by year isn't that much over Rafi's ouput. The only years where Rafi seems to have a lean period where the output decreased a little is 1976. So according to stats this dispels the notion that Rafi was gone and he made a comeback, since he was always there.
Now for the
'hits' angle, for the years 1970-1980, and based on the BGM charts, Rafi had hits every year from 1970-1980. 1970 and 1971 had major Rafi hits but surprisingly in 1971 he seemed to have very little presence on the BGM
charts which is quite surprising, maybe some manipulation took place. Let's list some 1971 films, Caravan, Mela, The Train, Pyar Ki Kahani, Gambler, Aap Aaye Bahar Ayee, Maryada, Rakhwala, Andaz, Mehboob Ki Mendhi, Mera Gaon Mera Desh etc. I don't think anyone would argue that the Rafi songs from these films weren't hits.
From 72-76 he had hits on the charts but the representation was not as much as 70 and 71 (even if the 1971 BGM list has very little Rafi, we can assume many of his hits were played on the radio that year). Songs that may have been hits may not have made it to the charts, but it doesn't mean they weren't hit songs.
Then from 77-82 Rafi's hits keep increasing, and particularly the years 1979-1982, according to the BGM trends it was a Rafi 'mini-wave' where Rafi was everywhere and very little of other singers around. So Kishore who found himself on the rise from 1971 and a few years after found himself facing the same situation from 79-82. Ofcourse Rafi ruled supreme for two plus decades where no other singer touched him so what happened in the years 1970-1980 don't really matter when talking about Rafi's greatness, but it still is interesting to discuss it.
Brinkster used to have a list of BGM songs from 1970-1980, including extra songs that weren't in the Top 30 or so but nonetheless hits. They took out those stats from the net so they can't be posted here.
I could easily post a BGM chart of the top hits of the year from 1970-1980, but that would not give the complete picture of Rafi's hits in particular years. Even if we do get charts that look complete, they may not be. We would have to have a really good source to list most of the hit songs of each particular year. I will look into this and try and find somewhat complete charts.
For example in the year 1976, Rafi had hits in Nagin, Charas, Jaaneman, Mausam, Bairaag, Laila Majnu etc. but the lists don't show all the songs from those films, so in other words they are incomplete. Also, if certain songs don't make it to a partcular list (like the ones on Google), it does not mean they weren't hits.
Hope this helps