Analyze the graphs below and answer the question that follows. Left, a bar graph titled Mexican Pesos per U S Dollar in 2008. The x-axis is labeled July, September, and November. The y-axis is labeled M X N 8 to M X N 14. July and September are over M X N 10. November is over M X N 12. Right, a bar graph titled British Pounds per U S Dollar in 2008. The x-axis is labeled July, September, and November. The y-axis is labeled 0.50 pounds to 0.70 pounds. July is near 0.50 pounds. September is 0.55 pounds. November is 0.65 pounds.
Data courtesy of RateX

The graphs above show the exchange rates between the US dollar and two other currencies in 2008. During the months shown, the number of Mexican pesos (MXN) in relation to one dollar rose from 10.2 to 13.1. The number of British pounds (£) in relation to one dollar also rose from .51 to .65.
Based on the graphs, did the value of the US dollar increase or decrease during these months?