Formulae needed to calculate cattle herd growth projection!

[Lady K]

Hello everyone! Help!

1. There are 61 cattle due to give birth in 2016 and then one calf per year thereafter.

2. There is a 45% chance of those calves being female.

3. Of those calves being female, they too would be in a position to reproduce once two years old, again having a 45% chance of giving birth to a female.

4. I'm trying to calculate how many cattle there would be in 2025.

How many columns, rows, calculations do I need and what would they be!

Is there a chance this could be easy for someone out there?

I've kind of made a start (can do Q1. and Q2).

......???

Thank you

		Actual	Projections
	Totals	61	122	244	305	366	427	488	549	610	671
	of which 55% = bulls		67	134	168	201	235	268	302	336	369
	of which 45% = heifers		55	110	137	165	192	220	247	275	302
		2016	2017	2018	2019	2020	2021	2022	2023	2024	2025

<colgroup><col style="mso-width-source:userset;mso-width-alt:4388;width:90pt" width="120"> <col style="mso-width-source:userset;mso-width-alt:2633;width:54pt" width="72"> <col style="mso-width-source:userset;mso-width-alt:1718;width:35pt" width="47"> <col style="mso-width-source:userset;mso-width-alt:1938;width:40pt" width="53"> <col style="mso-width-source:userset;mso-width-alt:1718; width:35pt" span="8" width="47"> </colgroup><tbody>
</tbody>

 

[Lady K]

ps. actually i need to know growth year-on-year - not just by 2025....