Here's an example of Italian singles' charts: 18 April 1964 - and its correlation to Brazilian charts of 7 months later. In other words... it took approximately between 6 months to one year for an Italian single to reach the Brazilian charts whenever it did.
Let's only take the singles that entered both Italian and Brazilian charts: John Foster's 'Amore scusami' reached #1 in Italy on 18 April 1964; after exactly 9 months 'Amore scusami' reached #1 in Brazil 9 on 5 January 1965.
Adriano Celentano never charted in Brazil for some mysterious reason. But take Mina's 'È l'uomo per me' (He walks like a man) which fell from the #1 position in Italy this week; 5 months later (September 1964), Mina took 'È l'uomo per me' to #8 in the Brazilian charts. Incidentally, this was the only hit Mina produced in Brazil. As with Adriano Celentano, Mina was a non-entity in Brazil.
Richard Anthony's 'Cin cin' was #1 in Italy in March 1964; 7 months later - October 1964 - it also reached #1 in Brazil.
Gianni Morandi's 'In ginocchio da te' reached #1 in Italy circa June; five months later - November 1964 - 'In ginocchio da te' reached # 5 in Brazil.
Nico Fidenco's 'Con te sulla spiaggia' went up the Italian charts in April 1964; 6 months later - November 1964 - 'Con te sulla spiaggia' reached #15 in Brazil .
Rita Pavone's 'Scrivi' went up 13 notches to #12 in April 1964 in Italy; in Brazil, Pavone took 'Scrivi' up to #1 - 3 months later (August 1964). The reason why it went all the way up to #1 was due to Rita Pavone's popular tour of Brazil in late June 1964. She had introduced 'Scrivi' 'live' on TV and as 'Datemi un martello' was slacking in sales, 'Scrivi' picked it up with a vengeance.
Bobby Solo's 'Credi a me' reached #13 in Italy in April. It played well on Brazilian radio waves but as 'Una lacrima sul viso' was still being played nationally - it stayed at #2 for 8 weeks circa June-July 1964 'Credi a me' hadn't much of a chance.
So from out of a list of the 30 best selling singles in Italy in April 1964 - Brazilians bought 8 singles which made a little less than one-third which is still impressive when one could hardly see any Italian hits on Brazilian charts just one year ago.
