(FORTUNE Magazine) – Most oil stocks look about as promising as a prairie full of dry holes. But thanks to a hybrid security, investors can try to make the most of one oil stock. Americus Shareowner Service Corp. of New York has done to Exxon stock what catalytic crackers do to crude: break it into components. Since last fall Americus has been offering ''trust units'' that enable investors to separate the two elements of the stock's hoped-for return -- capital gains and dividends -- and take the one they prefer. Americus, which pioneered the idea when it fissioned the stock of predivestiture AT&T (Personal Investing, January 9, 1984), arranges for interested Exxon stockholders to turn in shares in exchange for receipts called Americus Trust Units. The receipts are perforated down the middle into halves called Prime and Score. The Prime half entitles its owner to all dividends from Exxon stock until the trust terminates in September 1990, plus any appreciation in the stock price up to $60 a share. That price was picked so that Prime holders could enjoy a token amount of price appreciation; Exxon stock recently traded at $55. The Score half entitles its owner to all appreciation in Exxon stock beyond $60 a share but no dividends. Owners of the units can keep both halves -- tantamount to owning the stock at a slightly higher price reflecting the cost of creating the trust units -- or sell off one part and keep the other. Investors can also buy Prime and Score components, which trade separately but carry the same prefix symbol, ''A xon,'' on the American Stock Exchange. If oil prices heat up again and propel oil stocks, Score holders would rake in outsize gains. As the table shows, the yearly return to the Score holder zooms if the market price of Exxon stock significantly exceeds $68 a share when the trust terminates. Though the Score holder receives all appreciation beyond $60 per share, the price would need to reach $68 if he is to recover his investment in a Score unit, recently worth $8 on the Amex. Thanks to the built-in leverage of Score, an 8%-a-year rise in Exxon stock from the recent $55 would translate into a 20%-a-year return in the value of the Score unit. Given the nose dive in oil prices, most investors are anticipating less thrilling scenarios. By purchasing the Prime component, investors would fare better than stockholders if the stock goes nowhere or heads downward. If the stock price and Exxon's $3.60-a-year dividend remain unchanged through 1990, an investor who bought a Prime unit recently trading at $48 would pocket a 10.6% annual return, well above the 6.8% return the Exxon stockholder would get. If the stock falls but Exxon maintains its dividend, the Prime holder would suffer smaller losses than the stockholder. The Score holder, meanwhile, would take the biggest beating of all. If the stock price fails to reach $60 by the termination day, he loses his entire investment in Score units. Notwithstanding the risk, Scores have traded more heavily on the Amex than Primes. Since late 1983 the AT&T Scores have returned 254%, nearly four times more than the Prime return. The chart at left shows only the effects of changes in Exxon's stock price and assumes no change in the dividend, generally considered one of the industry's safest. Charles Cahn, an oil industry analyst at Sanford C. Bernstein & Co., reckons that if oil prices average $15 per barrel over the next couple of years, Exxon's dividend would escape a cut. If the company does pare its payout, the Prime holder's return would be better than the stockholder's.

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