Two years, the same counting window
Messi scored 91 goals in 69 appearances in 2012; Ronaldo scored 69 in 59 during 2013. Both records include competitive club matches and senior internationals from January to December. Messi’s total includes 79 for Barcelona and 12 for Argentina; Ronaldo’s includes 59 for Real Madrid and 10 for Portugal.
What changes at equal appearances?
Dividing goals by appearances gives about 1.319 for Messi and 1.169 for Ronaldo. At 50 appearances, those rates correspond to 65.94 and 58.47 goals. These calculated values describe the recorded scoring frequency; they are not matches that happened or a forecast.
A calendar year is not a season
Messi’s 2012 total spans parts of two club seasons, as does Ronaldo’s 2013 total. Do not compare either number with a league-only season. Use the calculator to change the sample, and inspect the original records before switching to minutes: equal time still leaves opponents and playing roles different.