The announcement of a price freeze for single fares strikes me as another example of a price cap; if it weren't for the intervention single fares would be higher. But what will its effects be? Yes, lower fares and a marginal reduction in the cost of living but will it result in overcrowding on the Tube, and is it promoting efficiency?

There are a variety of arguments to be had, you could start by looking at the PED of public transport in London as regards the effect on passenger numbers and then think about how this might affect the number of car journeys. You might look at the spillover effects for other sectors of industry in the capital too. But £123m represents quite an opportunity cost, so does this represent the best way for this money to be spent?