hatching % question ( math)

[okiehen]

This is a math question on hatching %.
I cant get in my head how to get the % hatched.
Okay lets use this as an example.
you started with 42 eggs
5 were clear at 8 days, do you count them ( I don't)
37 eggs went the full 21 days with chicks developed.
29 hatched out live chicks
8 eggs never hatched but had full term chicks in them
How do you get the % of your hatch?
Thanks

 

[the_eagle69]

eggs in - eggs out devided by eggs in x100 - 100 = % hatch and i would count the 42 in so you had 42-29=13/42=.31x100=31% - 100% =69% hatch rate Some one let me know if im wrong

 

[Tuffoldhen]

Quote:
I don't count clears, when I do my percentages of a hatch. Bloodrings or quitters I do but not clears.

Divide your 37 that you had on day 18 into the 29 live that hatched. 78%

 

[meriruka]

If you are not counting the non-fertile eggs, your rate is 29 divided by 37 times 100 equals 78%

 

[speckledhen]

If you count ALL eggs, even the clears, you are getting your Fertility Rate, not the hatch rate.

If you count only the ones that start developing, then you have your hatch rate.

Make sense? I removed 15 Blue Orp eggs from my last batch, all infertile. Had a butt fluff issue. I do not count those in my hatch rate.

Started with 42 eggs of several breeds. Of those, 17 were not fertile/clear. So I actually just had 25 eggs that I can get my hatch rate from. 21 hatched, so my hatch rate is 84%. Take 21 divided by 25.

 

[Clay In Iowa]

Quote:
That sounds like a personal problem..

Is it anything like "junk in your trunk"...

I kill myself....

 

[speckledhen]

LOL, not quite. Should have said the birds had a butt fluff issue, but since it messed up my plans, it became mine.

 

[okiehen]

Okay thanks that helps now. My husband was getting 77%
So every hatch we can take the number of hatched chicks
divided by the # of eggs that make it to 21 days . this get the right %
Thanks a bunch.

 

[twigg]

Quote:
Never count the clears.

The total eggs developing at day 7, divided by the number of hatched chicks.

So .... 29 / 37 = a respectable 78.4%

The reason clears aren't counted is simple. We are trying to maximise hatch rates, and considering improvements if the rate falls below around 95%.

The 8 dead-in-shell are an issue you can address.

If you count eggs that couldn't have hatched, you skew the figures unhelpfully.

 

[Matt A NC]

x = total number of eggs set
y = number of eggs that have development at day 10
z = number of hatched chicks that are viable. Any chicks that have to sadly be culled are not included in this number.


% Fertility = (y / x) *100%
% of hatch rate = ( z / y ) *100%

Matt