Lognormal properties of SGR 1806-20 and the Possibility of a Quiescent   Population of other SGR sources
  Monte Carlo simulations of long SGR event sequences based on lognormal distributions with a range of time intervals and intensity distribution parameters have been investigated. The main conclusions are that the majority of SGRs with properties similar to SGR 1806-20 have been detected but SGRs with mean waiting times much longer than SGR 1806-20 remain to be discovered. A large decrease in the probability for detection of an SGR source results from a relatively small increase in the distribution parameters obtained for SGR 1806-20. A new breed of experiments with very long observation times are required to search for this type of source. 
Brian McBreen, Kevin J. Hurley