When did the lower limit change?

[Ladkyis]

I have looked at all the threads in this section and none answer my question. With my keen ability to NOT find anything I am looking for on this here intarwebby I am turning to the people that know - the members of this forum. Here is my question.

When was the probate minimum estate value raised from £5 to £5000?

I am told that it was the 20th century but when?
I'll be back in half an hour to see the answer

[Lincoln Lad]

It appears to have been 1965 for small payments concessions, but stand to be corrected.
It was raised to £1500 in 1975 and to £5000 in 1984 where it remains today.