Sequential numbers for dates of the year Sequential Numbers for Dates of the Year Day of Month Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. 1 4 2345670 1 32 60 91 121 152 182 213 244 274 305 335 2 2 33 61 92 3 34 62 93 35 63 94 36 64 37 65 7 38 66 97 8 8 39 67 98 9 9 40 68 99 10 10 41 69 11 11 42 70 12 12 43 71 13 13 44 72 14 14 45 73 15 15 122 153 183 214 525 275 306 336 123 154 184 215 246 276 307 337 124 155 185 216 247 277 308 338 95 125 156 186 217 248 278 309 339 96 126 157 187 218 249 279 310 340 127 158 188 219 250 280 311 341 128 159 189 220 251 281 312 342 129 160 190 221 252 282 313 343 10 130 161 191 222 253 283 314 344 101 131 162 192 223 254 284 315 345 102 132 163 193 224 255 285 316 346 103 133 164 194 225 256 286 317 347 104 134 165 195 226 257 287 318 348 46 74 105 135 166 196 227 258 288 319 349 *For centennial years (those at the turn of the century), leap years occur only when the number of the year is divisible by 400 Thus 2000 was a lean