Sincethe1980s,especiallythemid-1980s,theimbalanceinthesexratioatbirthinChinahasbeenincreasingcontinuouslyandthesituationhasworsenedinrecentyears,accordingtothefourthandfifthcensusesin1990and2000.Thisissuehasdrawnwidespreadattentionfromthegovernmentaswellasacademia.Thefundamentalreasonfortheimbalance