Believe the Reuters story and you have an outage (partial outage, I'll wager) of, what, 8 hours? So that gives an annual uptime of 99.92%. That's not shocking and, yes, I'm assuming no more problems in the next year. Take it at the bank's 20 minute value and their uptime goes to 99.994%. Mind you, both these figures are more than acceptable - phone lines and terminal kit at retainlers are both far more likely to let me down, I suggest.
This gets a write-up because it happend on a Saturday - Sod and his laws, eh? If it had happend at 3am, the public would have been none the wiser!