Missing values

The recommended way of flagging "missing data" in WeSIS is by using an exclamation mark in the column user_na_values (cf. file formats). A detailed description of how to input and upload data containing "missings" can be found in the file upload guide. Such a way of flagging missing data is very generic to give the data providers room for defining "missings" in line with their intention. Note that the values have to be of the same type as the indicator's valid ones (i.e., numeric, string, or dates).

Still, below you can find a set of "missing codes" that have been agreed upon, and it is strongly recommended to comply whenever you see fit with your indicator to ensure consistency across WeSIS. If you need more codes for unveiling additional information on other aspects of "missingness" try to add codes that fit the already existing scheme (e.g., using -444, -555 etc.). In this case, please extend the list so that other projects can adopt your suggestion. Keep in mind that you still should document the use of any "missing codes" on each indicator page in the "Quick info box" under "Value labels" to also show up in WeSIS.

Suggested code	Description
-999	No information available: Data was unavailable or could not be found.
-888	Policy does not exist: Data was not collected due to knowledge that the policy either has not been implemented or has been discontinued.
-777	Not applicable: Data was not collected because it was not relevant for this specific country or policy.
9999	No information available: A modification to the code -999 to ensure that the user-defines missing value follows the date time format for indicators of which the scale == Date.
8888	Absence of a program: A modification to the code -888 to ensure that the user-defines missing value follows the date time format for indicators of which the scale == Date.
7777	Not applicable: A modification to the code -777 to ensure that the user-defines missing value follows the date time format for indicators of which the scale == Date.
-9999	Program not (yet) introduced (applies to indicators with introduction years only).