Batting Average

NASA's press-kit for the Mars Polar Lander has an overview of Mars missions, here's what I derived from that:

30 missions total:

16 USSR / Russia
13 USA
1 Japan

 

Results:

16 Failed (11 USSR, 5 USA)
12 Succesful (7 USA, 5 USSR)
2 In progress (1 USA, 1 Japan (in orbit round sun with propulsion problem))

First mission: 1960 USSR
First USA Mission: 1964 (Mariner 3)
First Succesful Mission: 1964 (USA, Mariner 4)
First Succesful USSR Mission: 1971 (Mars 3)
First Succesful Lander: 1971 USSR (Mars 3)
First Succesful USA Lander: 1975 (Viking 1)

Offered by Michel.