Value of the YTL on the front page

Please don't take this the wrong way, but the value shown for the YTL doesn't correspond with what is available in change shops.
Is this updated regularly as it was 2.35 (ish) last week and the front page of this site showed it at 2.6(ish)
Is this updated regularly as it was 2.35 (ish) last week and the front page of this site showed it at 2.6(ish)