22 Iran-Lebanon, Lebanon UAE, etc.) the approach cannot be employed.

Table 10 employs the available information to construct a 1990 matrix of the origins and destinations of regional intra-trade. As indicated Turkey plays a key role in this exchange accounting for 22 percent of all exports to the region and also serves as the destination of 26 percent of all other regional countries' exports. These figures understate Turkey's importance somewhat since, for political reasons, Cyprus is not reporting exports to Turkey in its official statistics. Saudi Arabia and the UAE combined account for about one-third of intra-regional exports and about 28 percent of all imports. Saudi Arabian exports to Turkey (mostly crude oil) constitute that single largest bilateral trade flow (about three quarters of a billion dollars) followed by UAE exports to Oman and Libya's exports to Turkey which (combined) are over one billion dollars.

What factors limit further trading opportunities among ME countries. Trade barriers are clearly important as an UNCTAD (1987) study showed that average tariffs in Syria, Turkey and Libya ranged between 27 to 34 percent and actually reached 100 percent in Iran. In addition, many of the middle-Eastern countries trade regimes were NTB ridden. Over 70 percent (by value) of Turkey's imports encountered some form of nontariff measure while this ratio was 99 percent in the case of Iran. In addition, there is also evidence that transport links within the region can be an important constraint to increased trade as most established liner conference routes follow a North-South pattern. One further possibility is that the export product profiles of some ME countries are so similar, particularly those of the oil exporters, that there are limited opportunities for intra-trade.

The "revealed" comparative advantage (RCA) index can provide some rough indication as to where opportunities for expanded intra-trade may exist. Countries with different revealed comparative advantage profiles should have more opportunities to trade than those whose RCA indices are similar. The revealed comparative advantage (RCA) of country i for product j is measured by the item's share in the country's exports relative to its share in world trade." The index (RCAij) has a simple interpretation. If it takes a value of less than unity (which indicates that the share of product j in i's exports is less than the corresponding world trade share) this implies that the country has a revealed comparative disadvantage in the product. Similarly, if the index exceeds unity the country has a revealed comparative advantage in the item. Table 11 presents RCA indices for Egypt and other regional countries exports of products classified in 9 broad product groups. In order to determine how RCA patterns were changing separate indices were calculated for 1970, 1980 and 1992. On request, the author will send more detailed three and four digit product indices for all regional countries to interested readers.

"That is, if x,1 is the value of country i's exports of j, and _Yj_ is the country's total exports its revealed comparative advantage index is: RCAjj = (xjj/X;) * _(X,wIXj)_ where the w subscripts refer to world totals.