Goldman estimates the current amount spent at Rmb860bn-Rmb900bn. Media reports in early July indicated that CSF lent Rmb260bn to brokerages to support stock purchases, bought Rmb400bn in stock directly, and invested another Rmb200bn in mutual funds.
Using an alternative methodology that compares fund inflows to the stock market from traceable sources with the total inflows necessary to keep the index at current levels, Goldman reached an estimate of Rmb900bn for national team investment in June and July.
"We believe the current market concern over the Chinese government's potential exit from its market support is probably overdone," Chengjie Liu and his colleagues wrote this week.
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"With the government having just spent a considerable sum to stabilise the market, it is too early for them to reverse course, especially given the still-skittish manner in which the market is trading."
The problem for the government is that it apparently has little to show for the money spent.
The Shanghai Composite Index was at 3,682 at midday on Thursday, just 9.2 per cent above the low point touched at the height of the selldown on July 9 and 28.9 per cent below the seven-year high of 5,178 reached on June 12.
On the other hand, the government is probably not comparing the market's current level to its recent highs and lows, but rather to the unknown depths the index might have plumbed had the national team done nothing.
Additional reporting by Ma Nan