1 d3.time.years = d3_time_range(d3.time.year, function(date) {

     2   date.setFullYear(date.getFullYear() + 1);

     3 }, function(date) {

     4   return date.getFullYear();

     5 });

     6 

     7 d3.time.years.utc = d3_time_range(d3.time.year.utc, function(date) {

     8   date.setUTCFullYear(date.getUTCFullYear() + 1);

     9 }, function(date) {

    10   return date.getUTCFullYear();

    11 });