Start with two weights and the actual dates
Current average daily gain is the change in weight divided by the actual number of days between the two readings. Keep both weights in the log instead of replacing the old one.
Use the dates from the scale notes. "About two weeks" can change the result enough to make the pace look better or worse than it was.
Each pace number answers a different question
Current ADG describes the interval that already happened. Needed ADG uses the pounds left and days left. Projected fair or show weight carries the recent pace forward as a scenario.
None of those numbers sets a target or guarantees an outcome. Enter the target weight and date from the current official fair or show rules. If the rules are unclear, ask the show office; an advisor, ag teacher, or Extension educator can help you locate the official source.
Update the projection after each weigh-in
A new dated weight gives you another interval to compare. If housing, ration, exercise, or other conditions have changed, USU Extension notes that the projection may be less accurate.
If a reading looks unusual, check the date, weight, and scale before using it. If the reading is correct, keep it in the log and add a note for your advisor. Do not use the calculator to make feed or animal-health decisions.
Bring the right questions to the advisor
Confirm the target against the current official fair or show rules. Bring the dated log to your advisor, and ask whether the latest reading should be checked again and when another weight would be useful.
BarnMath can clean up the arithmetic. The fair or show office handles official rules; take animal-care questions to a qualified advisor, Extension educator, or veterinarian, as appropriate.
Sources & local guidance
Source links checked July 31, 2026
Use this for project planning. This is not animal-health, nutrition, veterinary, or fair-rule advice.