Table: wta tier iv tournaments
[['tournament', 'also currently known as', 'city (s)', 'country', 'court surface', 'tier iv in', 'years'], ['rome', "internazionali bnl d'italia", 'rome', 'italy', 'clay', '1988', '1'], ['zurich', 'zurich open', 'zurich', 'switzerland', 'hard (i)', '1988', '1'], ['hamburg', 'rexona cup', 'hamburg', 'germany', 'clay', '1988 - 1989', '2'], ['new jersey', 'united jersey bank classic', 'mahwah , nj', 'united states', 'hard', '1988 - 1989', '2'], ['newport', 'virginia slims of newport', 'newport , ri', 'united states', 'clay', '1988 - 1989', '2'], ['san antonio', 'pilot pen tennis', 'san antonio , tx', 'united states', 'hard', '1988 - 1989', '2'], ['san diego', 'san diego open', 'san diego , ca', 'united states', 'hard', '1988 - 1989', '2'], ['sydney', 'medibank international sydney', 'sydney', 'australia', 'grass (1988) hard (1989)', '1988 - 1989', '2'], ['tampa', 'eckerd open', 'tampa , fl', 'united states', 'clay', '1988 - 1989', '2'], ['puerto rico open', 'honda classic', 'san juan (1988 - 1989 , 1991 - 1993) dorado (1990)', 'puerto rico', 'hard', '1988 - 1993', '6'], ['kansas', 'avon championships of kansas', 'wichita , ks', 'united states', 'hard', '1990', '1']]
Statement: there are 3 Clay Court Surface event that were held for exactly 2 Year each
Statement: the Medibank International Sydney is the only event to be played on multiple Court Surface
Statement: the average number of Year a Clay Court Tournament was played is 1.75
Statement: when the Puerto Rico Open was played in Dorado , the Hamburg Tournament was no longer being played
Statement: the Puerto Rico Open was played for more Year than the Rome and Tampa Tournament combined