Two vintages of BPE are not immediately comparable. Indeed, to estimate in the temporal comparisons what concerns a change of nomenclature, a change of source, a change of quality in the source or finally a real evolution of the services and equipment accessible in the ground is particularly complex.
However, in order to meet the needs of users of BPE, assessments are carried out to determine the conditions under which it is possible to use the BPE in evolution. Each year, a database of BPE in evolution is diffused. It covers two years spaced five years apart and is carried out in geography of the most recent year. Thus, the 2015-2020 BPE in evolution is in 2020 geography.

The diffusion of this database in evolution concerns a limited number of types of equipment, considered, over the period concerned, the most stable from the point of view of their definition, their outline, their construction, etc. It excludes the types of equipment relating to national education (in the field of education, only the equipment relating to agricultural education is disseminated in evolution). Thus, the 2015-2020 BPE in evolution relates to 127 types of equipment.
Following the expertise carried out by the BPE team, each type of equipment is characterized by the status "without reservation" or "with reservation", relating to its evolving use.