Taiwan coin dating
If you click on a year-link, you'll see how the date's characters are written on a real coin.
I think another reason is that 60 years is approximately the length of a human being's life; people have always been defining measurement units comparable to their own bodies' parameters (foot, yard etc.) or parameters of something related to their regular needs (kilogram, meter, pound etc.).
2013) is done by subtracting 543 from the Thai year.
The coins of the Chinese provinces didn't have a date as we understand it as a period of time elapsed since a moment defined as a time zero.
The 12 Earthly Branches are associated with the 12 signs of the Chinese zodiac (Rat, Ox, Tiger, Rabbit, Dragon, Snake, Horse, Sheep, Monkey, Rooster, Dog and Pig), and the Heavenly Stems pairwise are associated with the Five Elements (Wood, Fire, Earth, Metal and Water).
The year is specified by two Chinese characters in the Chinese calendar (see the table on the left), in the following order: [ numeral in the top of the cells indicates the ordinal number of this or that Gregorian year in a sexagenary cycle.
Kwang Hsu (also spelled as Kuang-hsü or Guangxu) was the last but one emperor of the Qing Dynasty.