Those born in late '79 or all the months in 1980 (except those late in that year) will affirm (especially those that are a touch absent-minded and have trouble with numbers of all kinds) that keeping score of one's age is quite easy in the first decade of the twenty-first century. All you need to do is to remove the 2 zeroes (usually in the middle). For example, what's the age in 2005? For most of the year, it will be 25. This is also true for the earlier decades, when in the Nineties, get rid of the mid-9s. We'll have to relinquish this after 2011, but till then, we can imagine a special date with the modern age.