Conditions not yet ripe for abolition of salt monopoly

I came across an interesting piece of news (or more accurately, non-news) today: conditions are apparently not yet ripe for abolishing the government's salt monopoly. (Report here.) This made me wonder whether the salt monopoly had therefore won the stakes for the longest-lasting government revenue source in Chinese history, given that the 2600-year-old agricultural tax had been abolished only late last year. But no: standard accounts put the salt monopoly at about 2500 hundred years of age, so it will have to last another century or so to beat the agricultural tax.