Monthly expenditures on ACEIs, ARBs, and overall renin-angiotensin drugs. (a) ACEIs, ARBs and renin-angiotensin drugs; (b) patented and off-patent ACEIs; (c) original branded and generic off-patent ACEIs. The arrows indicate the time points at which price adjustments were implemented. ACEIs, angiotensin-converting enzyme inhibitors; ARBs, angiotensin receptor blockers; NT$, New Taiwan Dollars (at an exchange rate of NT$30.39 to US$1 on June 30, 2008); PA2000, price adjustment implemented on April 1, 2000; PA2001, price adjustment implemented on April 1, 2001; PA2003, price adjustment implemented on March 1, 2003; PA2004, price adjustment implemented on November 1, 2004; PA2005, price adjustment implemented on September 1, 2005; PA2006, price adjustment implemented on November 1, 2006; PA2007, price adjustment implemented on September 1, 2007.