decided in 1105 to replace the Jiaozi with a new form of banknote called the Qianyin (錢引). Despite this inflation kept growing and a nominal mín was only exchanged for a handful of cash coins. The root cause of this inflation was attributed to the fact that the Song government didn't back their paper money up with a sufficient number of coins. The Song decided to raise the amount of stocked coins, yet in vain as it did not curb the inflation. Despite there only being around seven hundred thousand iron cash coins in circulation around 3.780.000 mín of banknotes were in circulation which rose to 4.140.000 mín, while an additional 5,300,000 mín in banknotes were issued in 1204 at which point between 400 and as low as 100 cash coins were accepted per 1 mín (of paper currency with a face value of 1000 coins cash). Local governments such as the Sichuanese government had to sell off tax exemption certificates, silver, gold and titles of its offices because of the inflationary policies around paper money. One of the causes of inflation was the outflow of currency to the neighbouring Jin dynasty to the north, which is why iron cash coins were introduced in border regions. In 1192 the exchange rate between iron cash coins and Jiaozi banknotes was fixed at 770 wén per guàn by Emperor Guangzong, but inflation would still remain an issue despite these measures. Despite the fact that all Jiaozi could be freely exchanged into cash coins their high denomination limited their use to large transactions. Rather than only being exchanged in coins, Jiaozi were often redeemed in Dudie certificates (度牒, a tax exemption certificate for Buddhist monks and nuns), silver, and gold. Eventually the Song government set an expiration date of 2 years for each Jiaozi, which in 1199 was raised to 3 years, after which they had to be either redeemed or replaced by newer series. The government officially restricted the amount of Jiaozi that could be in circulation to 1,255,340 mín, and were covered by only a fifth of that in copper cash coins. As these Jiaozi banknotes proved their usability private merchants began issuing their own notes in the north of the country and members of the military would receive their pay in paper money. Long after being abolished the Jiaozi continued to circulate until in 1256 a currency reform replaced the