1. With effect from 1 July 2012, the average wholesale charge that the visited network operator may levy on the roaming customer's home provider for the provision of regulated data roaming services by means of that visited network shall not exceed a safeguard limit of EUR 0,25 per megabyte of data transmitted. The safeguard limit shall decrease to EUR 0,15 per megabyte of data transmitted on 1 July 2013 and to EUR 0,05 per megabyte of data transmitted on 1 July 2014 and shall, without prejudice to Article 19, remain at EUR 0,05 per megabyte of data transmitted until 30 June 2022.
2. The average wholesale charge referred to in paragraph 1 shall apply between any pair of operators and shall be calculated over a 12-month period or any such shorter period as may remain before 30 June 2022.
3. The average wholesale charge referred to in paragraph 1 shall be calculated by dividing the total wholesale revenue received by the visited network or home network operator for the provision of regulated data roaming services in the relevant period by the total number of megabytes of data actually consumed by the provision of those services within that period, aggregated on a per-kilobyte basis on behalf of the relevant roaming provider or home network operator within that period.