Something you may not have noticed when reading your favourite book, magazine, journal or any piece of correctly typeset copy is the style of the numerals used within the text.
Oldstyle Figures
Old style vs lining/tabulating figures in Word – DSPACE
If you do not change direction, you may end up where you are heading, Episode 45 — Living Compass
Reed Words Campaign Against Living Miserably
Figures: proportional, tabular, lining and old-style figure sets
Text figures - Wikipedia
Demographic Change: Are Equal Living Conditions Falling to the Wayside?
Web Typography: Numerals – A List Apart
The Daily Heller: The Op-Ed is Op-Dead, R.I.P. – PRINT Magazine