Scaled data: select year, receiving and transmitting ionosonde and "Update"
In the table numbers of scaled ionogramms (max 360).

Month\Day 12345678910111213141516171819202122232425262728293031
January 288 265 251 200 173 288 282 287 264 269 271 284 286 284 288 282 247 235 241 232 278 288 288 287 288 286 288 285 288
February 281 288 287 286 288 288 288 288 288 288 288 285 204 287 281 285 287 283 288 288 288 288 287 288 288 286 288 288
March 284 288 288 288 288 287 288 280 288 283 287 282 281 271 287 286 287 288 285 285 278 272 279 288 287 270 287 285 288 288 285
April 283 288 288 263 286 268 274 280 270 280 254 266 247 217 122 8 6 2 156 274 257 258 260 280 284 287 285 282 288 265
May 278 254 255 256 197 279 273 195 279 268 280 274 265 271 277 198 276 251 228 267 258 220 260 209 264 247 263 85 14 15
June 9 7 135 253 259 274 154 4
July
August
September
October
November
December
Legend: No data Few (<100) Partial (100–199) Good (≥200)