Sunday to Thursday are counted as full working days, and Friday as half a working days, based on numbers of truckloads and workers passing through checkpoints. On 17 August, a number of workers were permitted to work in settlements and the Erez Industrial Zone. This ceased on 5 September. It is difficult to estimate with certainly the costs of closure, as many effects are indirect and lagged. Economic costs also vary with the duration and intensity of the closure, and are subject to seasonally.
Internal closures increase significantly the overall cost of closure.
The direct loss each working day can be estimated as a number of persons employed prior to closure, multiplied by the average wage. Direct losses are also accrued through losses of trade income. The IMF has projected that total exports for 1997 would be USD 366 million which, when divided by the 277 potential workdays in the year, yields average 1997 daily WBG export revenue of USD 1.3 million . Towards the end of August, a limited amount of goods were permitted access to Israeli markets. There are additional second round effects that reduced has on the sales and income of WBG businesses from whom workers purchase goods and services.