Hunch. To beat 0.5%, November prices would need to rise about 0.3% in the raw figures, which has happened in only 4 of the last 16 Novembers, all in years when the market was much stronger than now.
The 0.5% market resolves on the same Nationwide report: YES if the printed yearly change for November is 0.6% or higher, and NO if it is 0.5% or lower, even if Nationwide changes its October figure. Backups are the same as for the no-yearly-fall market.
We looked for cases where yearly growth in Nationwide's UK house price index fell two months in a row and landed between zero and 1%. Nationwide's monthly figures start in 1991. We found seven such months, from 2010 to 2025, and checked whether the next month showed prices lower than a year before.