I know this would be a reasonable amount of work but one could take advantage of the attributes of Excel and create a page that lists all models and grades, a master list if you will.
Then, make multiple copies, say every 5 years or two years or every year if one was so motivated. Edit each page for the models available for that time period and enter the appropriate prices (net selling price) for that year.
Then you wouldn't be comparing models available in 1900 at 1910 prices with models from 1923.
But it's a lot of work I'm sure, not a simple thing to publish or post for viewing, but it would be accurate in representing the choice a buyer had at whatever given point in time.
