Why do the reference years for the surveys used for the MPI differ by country? Isn’t it unfair to compare countries if the statistics in one case are five years older than in another?

The MPI relies on the most recent and reliable data available since 2005. The difference in dates limits direct cross-country comparisons, as circumstances may have improved, or deteriorated, in the intervening years. This is the reason why we do not rank countries based on the MPI value.