Passage: In league competitions, games may end in a draw. In knockout competitions where a winner is required various methods may be employed to break such a deadlock; some competitions may invoke replays. A game tied at the end of regulation time may go into extra time, which consists of two further 15-minute periods. If the score is still tied after extra time, some competitions allow the use of penalty shootouts (known officially in the Laws of the Game as "kicks from the penalty mark") to determine which team will progress to the next stage of the tournament. Goals scored during extra time periods count towards the final score of the game, but kicks from the penalty mark are only used to decide the team that progresses to the next part of the tournament (with goals scored in a penalty shootout not making up part of the final score).In competitions using two-legged matches, each team competes at home once, with an aggregate score from the two matches deciding which team progresses. Where aggregates are equal, the away goals rule may be used to determine the winners, in which case the winner is the team that scored the most goals in the leg they played away from home. If the result is still equal, extra time and potentially a penalty shootout are required.In the late 1990s and early 2000s, the IFAB experimented with ways of creating a winner without requiring a penalty shootout, which was often seen as an undesirable way to end a match. These involved rules ending a game in extra time early, either when the first goal in extra time was scored (golden goal), or if one team held a lead at the end of the first period of extra time (silver goal). Golden goal was used at the World Cup in 1998 and 2002. The first World Cup game decided by a golden goal was France's victory over Paraguay in 1998. Germany was the first nation to score a golden goal in a major competition, beating Czech Republic in the final of Euro 1996. Silver goal was used in Euro 2004. Both these experiments have been discontinued by IFAB.

Question: When did the IFAB experiment with not requiring penalty shootouts?
the late 1990s and early 2000s