Member States shall select by 30 June 1994 at its latest a sufficiently large number of permanent observation plots in their country. The maximum number of these plots should in principle not exceed 20 % of the number of national plots of the Community's 16 x 16 km gridnet (Regulation EEC No 1696/87). Member States with a limited number of plots of the Community's gridnet, are allowed to select a larger number of permanent plots under the condition that the number shall be limited up to 15 plots.