Sorry if this is a dumb question, but whenever I want to look up the US treasury bond, I can only find the historical chart for its yield. But how could I find its historical price ($1183.28 as in the picture. The price changes from time to time)? Has anybody/website ever made a chart documenting the historical price, not just the yield, of US treasury bond? (I suppose it is not very easy to compute the price by hand.)
Price is what you pay, yield is what you get. The advantage of looking at yields is that they make it easy to compare different bond issuances.
The price of a bond will depend on the face value (generally $1,000), coupon rate (if any), payment frequency (annual/semi-annual), time to maturity, and discount rate.
If we're talking about the dirty price, rather than the clean price, we'll also need to account for the accrued interest since the last coupon payment.
If you have the required inputs, you can compute the price using the present value function of your calculator or spreadsheet software.
That said, Treasury Direct let's you request historical prices by date.