That is a very strong statement. What you are saying is that the demand for gold did not change. But how can you determine that? Economists use the price system. But if you look at the dollar price you see that the price went up. The conclusion should be that the demand for gold (golds value) went up. Or maybe the dollar went down? To determine if gold retained it's value you need to o compare it to other products. For a certain basket of goods that cost X grams of gold Y years ago, how much gold do I need now to buy the same basket. The problem is that after a long enough years you can't compare the baskets. In the 70s TV was black and white. In the 1920 transportation was by horse and buggy. My point is that it's not as simple as you put it.