If we take just the 20th and 21st centuries, then these years have the same day/date combination as 1991:
1901, 1907, 1918, 1929, 1935, 1946, 1957, 1963, 1974, 1985, 1991, 2002, 2013, 2019, 2030, 2041, 2047, 2058, 2069, 2075, 2086 and 2097.
2003 was the last year before 2014 that had the same calendar. Before that there was 1997 and 1986.
1983, 1994, and 2005 all had the same calendar as 2011.
The calendar year 1994 repeats in 2000 because both years start on the same day of the week and have the same leap year configuration. Specifically, 1994 was not a leap year, and January 1 fell on a Saturday. Since 2000 is also a non-leap year starting on a Saturday, the days of the week align perfectly, resulting in the same calendar layout. This phenomenon occurs every 28 years, which is why 1994 and 2000 share the same calendar.
2001, 2007, 2018, etc.
The most recent year with the same day-date correlation as 1980 was 2008. The next year with the same day-date correlation as 1980 will be 2036.
2013, 2019, 2030, etc.
1999 was the last year before 2010 with the same calendar.
The calendar for 2009 was the same as 2015
April & July for all year and Jan and Oct for non leap years
The 2012 calendar year will repeat in the year 2040. This is because the Gregorian calendar repeats every 28 years. In the year 2012, the days of the week matched up with the days in 2040, meaning the calendar will be the same for both years.
1984 was the last year that had the same calendar as 2012.
1984 was the last year with a calendar the same as 2012.
2018
A calendar of 1991 can be found at calendarlabs.com
The last year that had the same calendar as 2012 was 1984, and the next one will be 2040.
2003 was the last year before 2014 that had the same calendar. Before that there was 1997 and 1986.
2022 is the next year after 2011 to share its calendar.