The number of infants with low birth weight fell from 16 per 1000 to 0.3, a 15% drop in total over the same timeframe. Between 2005 and 2010 as compared to the 1985–1990 period, infant mortality per 1,000 births also fell from 152 to 109.6. Significantly, maternal mortality per 100,000 births fell from 1,600 in the pre-war 1985–1990 half-decade to 1,100 in the 2000–2005 period. The number of physicians per 100,000 people also rose from 3.4 to 4 over the same timeframe, as did the percentage of the population with access to sanitation services, which increased from 18% to 26%.. In which period did the percentage of the population with access to sanitation services increase?