down the pan

Haruki Murakamiの小説 "South of the Border, West of the Sun" を読んでいます。

"Consider yourself lucky. Me and companies don't get along. I don't think you'd find it any different. Eight years working there convinced me. Eight years down the pan. My twenties - the best years of all. Sometimes I wonder how I put up with it for so long.

"down the pan" の意味を調べます。

・Farlex Dictionary of Idioms: Completely and irreversibly wasted, lost, or destroyed. Primarily heard in UK.: In an instant, we saw all our hopes for our business go down the pan.
・Wiktionary: (idiomatic, UK slang) Synonym of down the toilet: wasted; irretrievable.
・Phrase Finder: If something has gone ‘down the pan’ it is wasted and unrecoverable.: The pan is the lavatory pan. This phrase is of UK origin and is fairly recent. The first record of it in print is in the 1961 edition of Eric Partridge’s A Dictionary of Slang and Unconventional English.

イギリス英語のスラングでした。