Speculating with Stock Index Futures_英语论文

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● 茆懿心博士Dr Jennifer Mao　Suppose the settlement prices for the SiMSCI Futures September contract over the period from the 24th to the 31stof August are as shown in Column (3) of the accompanying table. Since Mr Tan buys one contract at 180.0 on 24 August and the settlement price at the close of that day's trading is 182.4, he makes a gain of 2.4 points. The profit of $480 (being $200 x 2.4) will be credited to his margin account.　Suppose Mr Tan remains bullish on the Singapore stock market and does not close out his position till 31 August. Then, his daily gain (or loss) will be determined by the settlement price at the end of each day. This daily computation of profits and losses will be carried out until the position issquared off by an offsetting trade. In the table, Mr Tan's daily gains (or losses) are shown in Columns (4) and (5). 　After each day's settlement, if the balance of his margin account is above the "maintenance margin" level of $4,000, Mr Tan will not get a "margin call". Once the balance touches $4,000, however, Mr Tan must replenish his margin account to the initial margin level of $5,000 if he does notwant his position to be forced-closed. As such, in our example, Tan will need to meet a margin call for $2,240 whenthe index falls 6.4 points on 27 August and his margin account dips to $2,760.　Suppose Mr Tan finally decides to close out his position on 31August at a price of 165.2 points. After deducting his final day's loss of $960, he can withdraw the $4,280 left inhis margin account.　Over the eight-day period, Tan loses a total of $2,960 (= $200 x (165.2-180.0)). This can be verified by his cash flows: Altogether he pays $7,240, the sum of the initial margin $5,000 and a margin call of $2,240. However, at the end of the game, he only gets back $4,280.　On total cash outflows of $7,240, the loss of $2,960 amounts to a 40.9% loss while the index drops by a relatively small 8.2%. Such is the power of "leverage" or "gearing", i.e., being able to bet on something worth $36,000 with only a capital of $7,240.　When a speculator bets wrongly, gearing blows up the damage. If the bet is placed on the right side of the table,the reward will be similarly magnified. If Mr Tan foresees the market downtrend correctly and sells the contract at 180.0 on 24 August and buys it back at 165.2 on 31 August, his investment will be just $5,000 (since he will not face any margin calls). He will have a profit of $2,960, a 59.2% rate of return.　First of all, as with all speculative financial activities, profits are made when the bet is proven right; losses result if the bet turns out to be wrong. To speculateon broad market movements using SIF, one must be aware of the blow-up effect of gearing mentioned above.　Compared with an actual investment in a basket of shares, taking a long position in SIF has another shortcoming. When the market drops, both shares and the long position in SIF will lose value. However, shares do not "expire" (unless thecompany goes bankrupt and is liquidated) and if an investor with the holding power decides to hold on to the shares, he can always do so. This however does not apply to SIF. Each SIF has a "maturity date" when any outstanding position in that contract must be closed. In other words, one can choosenot to realise paper losses when one invests in shares; but,one will be forced to realise such losses with SIF contracts. Of course, investors still bullish or bearish on the broad market can always place their bets on other SiMSCIFutures contracts still outstanding.　First of all, as illustrated above, a bullish investor needs only a relatively small sum of money to bet on the broad trend of the 35 stocks included in the MSCI index. Forthose who are bearish about the broad market movement, a short position in SIF allows them to profit from this view if it turns out to be right.　Secondly, for investors who have a view on the broad market, but are not interested in picking specific counters,SIF is an ideal instrument.　Thirdly, the transaction costs for trading SIF contracts will not be proportional to the contract value. Instead, it will be a flat fee per contract for a round trip. There is no doubt that the actual cost figure will be significantly lower than the commissions and clearing fees incurred for SES stock trading.　Finally, with the low required capital and transaction costs, an investor can get in and out of the market easily and cheaply. If there is good liquidity of SiMSCI Futures tostart with, a virtuous circle can set in to draw in more hedgers and speculators, leading to even lower transaction costs and higher liquidity.(Part two of two)(The writer is Senior Lecturer of the Department of Finance and Accounting, NUS & a resource panellist of SPH's Chinese Newspapers.)如何以股价指数期货投机？　　假设9月30日到期的摩根新加坡指数期货从1998年8月24日到8月31日的结算价格有如附表第3栏所示。　　张三在8月24日以180.0点的价格买入该期货一只。当天的结算价格182.4比买入价涨了2.4点，值480元。在每日结算制度下，张三保证金户头会增加480元。　　假设张三在8月25日至28日这段时间里还是看涨新加坡股市，所以对该期货没有采取任何行动。根据交易所每日公布的结算价格，张三每天的损益点数就如附表第4栏所示，每天的损益金额则列于第5栏。　　每天结算、把损益过帐到保证金户头后，只要保证金余额高于规定的“维持保证金”水平，盘口持有人就不会收到“补仓通知”(margin call)。张三的保证金户头在8月24、25、26日的结算后余额都在4000元以上，所以无需补仓；超出5000元的部分甚至可以提用（如做为其他合约的交易保证金）。　　张三的盘口在8月27日遭受了1280元的损失，造成结算后的保证金余额只剩2760元，低于维持保证金4000元，所以需要补仓。每当补仓时，必须将保证金余额填到初始保证金5000元的水平，所以张三必须再拿出2240元。　　假设过了周末之后，张三不再看涨新加坡股市，决定不再继续冒险，他于是指示期货经纪以165.2的价格卖出该期货。换言之，张三“盖盘”或“清盘”了。盘口一旦盖掉了，就再也没有损失的风险了，交易所及经纪商也就无须担心张三赖帐了，所以张三可以取回保证金户头里的余额。　　现在我们可以以三个角度来计算张三此番期货投机未扣除交易成本前的损益。一、把附表第5栏的“每日损益金额”合计，共损失2960元。二、以180.0买进、165.2卖出，损失14.8点，每点200元，共损失2960元。三、开盘时支付初始保证金5000元，后来补仓2240元，共付出7240元；盖盘后只取回4280元，净损2960元。　　这个损失相当于他动用到的资金7240元（5000元加上补仓2240元）的40.9%。在同一时间里，此指数期货的价格从180.0点跌到165.2点，跌幅8.2%。这验证了期货“以小博大”的特性——注下对了的话，可以放大报酬率；注下错了的话，也膨胀了损失率。　　有了“后见之明”，我们当然知道了张三对股市走势是看走了眼。由于他把赌注下错了边，所以赔了钱。如果他看对了，也就是他在8月24日预测股市将下滑，那么，他应该卖指数期货，也就是开“卖空盘口”(short position)。　　假如张三在8月24日以180.0点的价位卖出一只9月期货，再于8月31日以165.2点买进清盘，他未扣除交易成本的投机利润将是2960元。由于他不会接到任何补仓通知，他的投资就是初始保证金5000元。换句话说，在前后10天不到的时间里，他的报酬率将是2960÷5000＝59.2%。　　从上面的例子里，我们可以清楚地看到股价指数期货的一些优缺点。在缺点方面，第一、由于买卖者只需支付初始保证金及补仓，期货具有比以按金交易(margin trading)买卖股票更高的杠杆作用。当赌注下错边时，它的杀伤力也更大。　　第二个缺点是，不像股票，指数期货是有到期日的，而且到期日多半很短，近的就在当月月底，远的也不过就是一年又两个月以后。（当然，如果此合约受到市场欢迎，只要有这方面的需求，交易所可推出更远的合约。）当我们自资买进股票、股价却不断下跌时，“不服输”（因此，不肯放手）的人可以把股票“收”起来，只要公司不倒，价格反弹的机会总是在的。期货就不同了，到期日一到，就得来个输赢总算帐。愿意继续投机的投资者只能把目标转到其他尚未到期的期货去。　　优点方面，第一、一个投资人只需有支付初始保证金的闲钱，就可以考验一下自己的“慧眼”了。（只有“闲钱”才适合拿来投机；万一赔了，虽然负报酬率的数字看来很大，金额并不是太大。新加坡国际金融交易所不论对业务量是多么地用心争取，也不会希望有人因为盲目投机产生巨损而跳楼自尽。）　　第二、只想搭“股市列车”的投资人无需花功夫从数百家挂牌公司中精挑细选出投资对象，节省了许多打探