German long distance trains are 64% on time because up to 5 minutes delay are not counted for the statistics and guess what? Trains that never arrive (due to being way too late to continue their journey or because of technical problems on the trains or track system) are not included in the statistics either!
For the non germans: say a train is supposed to go from Munich over Hamburg to Kiel, and then return back to Munich. If that train accumulates so much delay that it could not even start the return trip on time, it might just stop in Hamburg, dump all the passengers, and turn around heading to Munich.
Now the skipped stops don't count as delayed, since the train never stopped there, the train is on time again for the return trip, and hundreds of passengers are pissed off and stranded somewhere they never wanted to be.