2015 in the context of 2010s

A common year starting on Wednesday is any non-leap year (a year with 365 days) that begins on Wednesday, January 1, and ends on Wednesday, December 31. Its dominical letter hence is E. The current year, 2025, is a common year starting on Wednesday in the Gregorian calendar, and the next such year will be 2031, or, likewise, 2015 and 2026 in the obsolete Julian calendar, see below for more. This common year is one of the three possible common years in which a century year can begin on, and occurs in century years that yield a remainder of 200 when divided by 400. The most recent such year was 1800, and the next one will be 2200.

Any common year that starts on Wednesday has only one Friday the 13th: the only one in this common year occurs in June. Leap years starting on Tuesday share this characteristic.

A common year starting on Thursday is any non-leap year (i.e. a year with 365 days) that begins on Thursday, 1 January, and ends on Thursday, 31 December. Its dominical letter hence is D. The most recent year of such kind was 2015, and the next one will be 2026 in the Gregorian calendar or, likewise, 2021 and 2027 in the obsolete Julian calendar, see below for more.

This is the only common year with three occurrences of Friday the 13th: those three in this common year occur in February, March, and November. Leap years starting on Sunday share this characteristic, for the months January, April and July. From February until March in this type of year is also the shortest period (one month) that runs between two instances of Friday the 13th. Additionally, this is the one of only two types of years overall where a rectangular February is possible, in places where Sunday is considered to be the first day of the week. Common years starting on Friday share this characteristic, when Monday is considered to be the first day of the week.