Table:
text: VMV-class patrol boat
Vessels of the class
Vessels of the class
Ship Launched Location_ Speed Fate
VMV-1 1930 Germany 25 knots Decommissioned 1950
VMV-2 1930 Germany 25 knots Decommissioned 1950
VMV-3 1930 Helsinki , Finland 23 knots Lost (burned) 1931
VMV-4 Former: Sterling 1916 Norway 16 knots Retired 1939
VMV-5 1931 Uusikaupunki , Finland 23 knots Decommissioned 1959
VMV-6 1931 Uusikaupunki , Finland 23 knots Decommissioned 1960
VMV-7 1932 Turku , Finland 23 knots Lost (burned and sunk) 1933
VMV-8 1935 Turku , Finland 23 knots Lost (sunk) 1944
VMV-9 1935 Turku , Finland 23 knots Decommissioned 1960
VMV-10 1935 Turku , Finland 23 knots Lost (sunk) 1944
VMV-11 1935 Turku , Finland 23 knots Preserved

Question: What is the average launch date of vmv-1 ship among VMV class patrol boats in Germany?