Something else to think about is the way different resistors and other components have been graded over the decades. For instance there were manufacturing appr

Something else to think about is the way different resistors and other components have been graded over the decades. For instance there were manufacturing approaches where a target value was produced for a large number of components, but the manufacturing tolerance was a very wide +/- 20%. The parts were then graded individually into the 1%, 5%, 10% and 20% bins, marked and priced accordingly. If you then specified the lowest-cost 20% parts, none of them were actually any closer than 10% to their nominal value.