This International Standard is applicable to all types of libraries in all countries. Limitations on the applicability of individual performance indicators are listed in the scope clause of the description of each indicator (see annex B). Indicators may be used for comparison over time within the same library. Comparisons between libraries may also be made, but only with extreme caution, taking into account any differences in the constituencies of the libraries, with good understanding of the indicators used, and careful interpretation of the data (see 5.3.5). This International Standard does not include indicators for the evaluation of the impact of libraries either on individuals or on society. Performance indicators are not specified for all services, activities and uses of the resources of the library, either because such indicators had not been proposed and tested at the time of formulation of this International Standard, or because they did not fulfil the criteria specified (see 4.2). This International Standard is not intended to exclude the use of performance indicators not specified in it (see clause 6). Throughout the text, the names of indicators are printed with initial capitals for significant words, e.g. Library Visits per Capita. This helps to distinguish the names from supporting text