Number of Calls vs Number of History Slots vs Number of Attempts

The Number of Calls is stored in 5114.3. Every time a phone record is picked up the Study Server/Survent and given a call status that is one that records a history (not 201-300), this counter is incremented. It is informational only and is not used to resolve numbers or determine when the next attempt might be made.

The Number of History Slots used is stored in 5117.3. Every time a phone record is picked up by the Study Server or Survent and given a call status that is one that records a history (not 201-300), this counter is incremented. The information about that call (who made it, what the status was, and when it happened) are recorded in the next history slot that is available. The maximum number of history slots is set in the phone header. If more calls are made to the record than history slots are available, the system will then do what is call “roll phone history”. It keeps the first call in the first history field, but it will roll the last n-1 calls into the last n-1 call history slots, where n is the maximum number of call histories that were allowed.

For instance, if 7 calls are made to a number, but the maximum number of histories is set to 5, then there will only be information about the following call numbers: 1, 4, 5, 6, and 7.

The Number of Attempts is stored in 5005.5. This setting is used to determine when a number will be resolved due to the maximum number of attempts being met. Every time a phone record is picked up by the Study Server or Survent and given a call status that is one that records a history (not 201-300), this counter is incremented with the exception of what happens with busy attempts. When a busy status (102, 681-698) is returned by the system it DOES count as an attempt. However, if the setting for Busy to No Answer is greater than 1, then the subsequent call(s) will NOT count as an attempt if they are the 2nd+ attempt due to that setting.

For instance, if a call is made to a number and it is busy and then another call is made to that number 15 minutes later because the Busy to No Answer setting is 2 and the Busy Rescheduled setting is set to 15 and that call ends up as a No Answer, it will only count as 1 attempt, although it will count as 2 calls and use up 2 history slots.

Also, by default if what should be the last attempt to a number is a call back (status 104,105, 161-170, 601-679), then the system will try to make another attempt even though this call should have been the last attempt. The theory is the respondent has agreed to accept a call-back so it is worth trying one more time. When the number is called again, if will again only be resolved if a non-call back status is returned. In theory, you could continue to call that number indefinitely.

You can override this behavior and cause call-backs to be resolved when the maximum attempts setting is hit by using the phone header option:

TIMED_CALLS_USE_MAXIMUM_ATTEMPTS = YES

Unless you are using both the above setting and also set the busy to no answer setting to 1 (not usually wanted by the phone room), then you always have the chance of having more phone histories than call attempts. If you do not want to ever lose (m)any histories, then you should make sure the number of histories setting is at least a few more than the maximum number of attempts. However, in general you do not want to make the maximum number of history slots allowed arbitrarily large as the disk space for the slots have to be allocated up for all records and each slot can require up to 100 bytes of disk space. If you have a large phone file with 50K records, adding just 5 history slots can make the file 25 megabytes larger.

If you zap/erase records, then the number of attempts counter and the number of history slots used will be reset to 0, but the number of calls counter will not be. If you do a zap,last then the attempts counter is decremented by 1 (although it remains 0 if it was already 0) and the last history slot information is removed and that counter is also decremented by 1 (it also will not go below 0). If you do a zap,save or a zap,last,save then only the number of attempts counter is effected. Using the save option can also cause more histories to be used on a record than the maximum attempts setting would normally allow.

Although this option is seldom used there is a way to also remove histories in the Survent interview by using the command:

!PHONE, ERASE_ALL_CALLHISTORIES

It works the same as a zap would in that it resets the number of attempts counter to 0 and removes all the call history information. It does not change the number of attempts.

NOTE: If you use one of the call statuses that do not record a history (201-300), then none of the above counters are effected. You will only be able to track such instances either in the last 8 operations field (5320.16) or in the server LL log file.