invert-2004-2006-phs-bands

Date: 2026-09-09. Status: implemented.

Decision. The eight PHS population-weighted bands for SIMD 2004 and 2006 are re-derived as 11 - decile and 6 - quintile so that 1 means most deprived in every edition. Ranks and the Most15pc and Least15pc flags are never inverted.

Reason. PHS publishes those two editions with 1 = least deprived, the reverse of every later edition. The PHS deprivation guidance requires the reversal to be handled; handling it once upstream prevents every analyst handling it separately.

Evidence. PHS 2004 rank 1 has published country decile 10 and official government decile 1. Reversal is exactly invertible; raw files are pinned.

Columns (16): simd2004_pw_ca_decile, simd2004_pw_ca_quintile, simd2004_pw_hb_decile, simd2004_pw_hb_quintile, simd2004_pw_hscp_decile, simd2004_pw_hscp_quintile, simd2004_pw_scotland_decile, simd2004_pw_scotland_quintile, simd2006_pw_ca_decile, simd2006_pw_ca_quintile, simd2006_pw_hb_decile, simd2006_pw_hb_quintile, simd2006_pw_hscp_decile, simd2006_pw_hscp_quintile, simd2006_pw_scotland_decile, simd2006_pw_scotland_quintile