But keep in mind that for the last 2 years the GBP has been on a general downwards trend [0], and in the lead up to the vote (the preceding 10 days) there was a rally that boosted the value by at least half of what was lost.

The raw value of the figures seems scary (lowest value in 30 years, value of the pound dropped by 13%), but the reality is that after dipping very briefly to "the lowest level in 30 years" the GBP is currently about the same as it was in Feb this year and the value is down 4% from 2 weeks ago (not great, but nothing like a 13% downwards plunge).

Edit: Also worth noting, the FTSE is up from the start of the month, and roughly equal to what it was at the start of the week. Aside from a big dip and a bounce, it's literally like nothing happened [1].

0: http://www.xe.com/currencycharts/?from=GBP&to=USD&view=2Y

1: https://uk.finance.yahoo.com/echarts?s=^FTSE#symbol=^FTSE;ra...