This has happened in the past but I finally got a screenshot of it. Sometimes in my accountant, the amount of horses entered into a show in the Horse Expenses section and then the amount of horses shown in the winnings in the Horse Income section do not match up. No horses are scratched. I blocked out the money aspect on my screenshot but it makes it difficult to calculate my profits when the numbers are not accurate. I don't know what causes it since it's an on and off thing. I use Safari.

There is nothing wrong. It seems that only the days you entered them and the days they got shown are different.

73 + 25 = 98 horses in member shows
Seems you entered them on the same day, but into shows that ran on different days ;)

360+ 543 = 903 horses entered
471+432 = 903 horses shown

Same here.
Maybe you enter your horses at a time where some horses still get shown on the one day and some get shown on the next one ;)