No matter who has good or bad calligraphy, some are valuable and some are not valuable, some are expensive and some are relatively cheap, so we cannot generally use square feet to talk about it, we can only say how much a certain calligraphy is. Money per square foot. Runge doesn't have any accuracy, it's just a reference. It mainly depends on his own judgment and understanding of his calligraphy and painting, as well as the market hype at the time. A calligraphy and painting will have different prices in different places, at different times, and in the hands of different auctioneers. Therefore, it is difficult to judge, let alone an absolute price; besides, any personal evaluation is only one-sided and personal point of view. Featured, famous, or wanted by someone special, these may make the price higher. As long as it's in good condition, it has collection value. It’s my own opinion, please forgive me if I’m wrong!