Over the last 20 years, New Zealand has experienced faster growth in real house prices than any other OECD country. In the space of a generation, housing has gone from being abundant and reasonably affordable to being scarce and prohibitively expensive. This report analyses how prices and supply have changed over 90 years from the 1930s to the 2010s, to understand whether more rapid price increases in recent decades are due to faster growth in housing demand, or slow housing supply responses.