Abstract: Call traffic in a stored program controlled telephone switching system is controlled by performing code gapping on telephone calls to a particular called customer. Code gapping is performed by limiting the rate at which successive attempts may be made to complete all or part of a call to the particular called customer which is identified by a called customer code, such as a Plain Old Telephone Service (POTS) called customer directory code. A Minimum Time (MT), such as 10 seconds, is prescribed as the MT for the POTS number. A record is made of the Last Clock Time (LCT) at which the last earlier allowed attempt was made to complete a call to the POTS number. The Present Clock Time (PCT) is noted as the time at which completion of a subsequent call to the POTS number is presently desired.