Collect the price earnings ratios for three companies in the same country for the years 2009 to 2018. You can use the data set provided for the London Stock Exchange or pick your own companies. The data set has a sample of companies from the FTSE 100, and the P/E ratios are for the end of each year from 2009 to 2018. The data also gives the P/E ratios for the FTSE 100 index. 

Discuss the factors that might explain the differences in the price earnings ratios of the three companies you have chosen and the changes that have occurred in their price earnings ratios over the period. (Choose companies with a range of P/E ratios, to give you one with a relatively low value, one with a relatively high value, and another with a middling value. Although not necessary, firms from the same industry helps for comparison reasons) 

You should use the insights provided by valuation models on the determinants of the price-earnings ratios in your discussion, but you should also discuss the role of any other factors that might influence the reported values of price-earnings ratios of the companies you have chosen?