+ plp::DataRange *get_monthly_summary(plp::Date *date, EnumSummaryCalculationType calc_type);
+ /**
+ * Get summary data calculated from the daily data items that is meaning full.
+ * Depending from the device type, it may be daily mean value, daily delta, highest value, etc...
+ */
+ plp::DataRange *get_monthly_summary(plp::Date *date);
+ plp::DataRange *get_monthly_summary(plp::Date *start_date, plp::Date *end_date);