Verbing questions

[Paul McFedries]

I had a discussion recently in which the topic of verbing (turning nouns
into verbs) came up. Two questions were raised to which I'd be interested in
knowing the answer:

1. What is the oldest verbed noun that has survived into the present day?
2. As anyone ever tried to figure out what percentage of verbed nouns become
a permanent part of the language?

I'd appreciate any answers/pointers/speculations.

Paul