The bill for meeting the Millennium Development Goals could turn out to be far bigger than donor countries are prepared to foot, going by estimates from international agencies on the eve of the International Conference on Financing for Development. A study by the British NGO Oxfam ahead of the conference to be held in Monterrey in Mexico from March 18 to 22 estimates that an extra 100 billion dollars a year will be needed. ''On present trends these goals will be missed by a wide margin,'' Oxfam says in its report 'Last Chance in Monterrey'.