Hello everybody

I've been thinking lately about how to compare my strength when lifting, to measure how good is my performance.

I heard last week about some strength standards 100kg(220 lb) x 5 reps BP, 142kg(315lb)x 5 reps Squat and 225kg (500lb) x 5 reps Deadlift.

I don't understand why to use a fixed figure. Would you consider somebody 225lb lifting 300lb deadlift as strong as 135lb lifting the same weight?

Is there a golden ratio weight lifted vs body weight to use as a more reliable reference?