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MERCY PRIMARY SCHOOL

Roll number: 03220F Chapel Lane, Birr, Co. Offaly

School details

Address: Chapel Lane, Birr, Co. Offaly (R42TX89)
Email: [email protected]
Phone: 0579120259
Principal: Barbara Hanamy
Ethos: Catholic
DEIS: Y
Irish classification: No subjects through Irish
Gaeltacht: N
Island: N
Local authority: Offaly County Council
School patron: Bishop of Killaloe
School type: Ordinary with Special Classes
School level: All-Through School
Planning area: Birr

Class size history

Mainstream class group data is shown separately from standard/year-group enrolment data. The source does not identify which standard/year group each class group belongs to.

Average class size

16.88

2025/26

Mainstream classes

2025/26

Largest class group

2025/26

Classes with 30+ pupils

2025/26

Class group metrics trend

Class group metrics by year

Year	Mainstream class pupils	Mainstream classes	Average class size	Largest class	Classes 30+
2006/07	206	10	20.60	29	0
2007/08	213	10	21.30	29	0
2008/09	215	10	21.50	30	1
2009/10	208	10	20.80	30	1
2010/11	205	10	20.50	30	1
2011/12	215	10	21.50	31	1
2012/13	219	9	24.33	35	2
2013/14	210	9	23.33	30	1
2014/15	191	9	21.22	29	0
2015/16	171	8	21.38	29	0
2016/17	157	8	19.62	24	0
2017/18	155	7	22.14	30	1
2019/20	139	7	19.86	24	0
2020/21	138	7	19.71	24	0
2021/22	120	7	17.14	24	0
2022/23	127	7	18.14	25	0
2023/24	113	8	14.12	18	0
2024/25	133	7	19.00	28	0
2025/26	135	8	16.88	21	0

Data highlights

Key numbers to spot outliers or notable changes.

Biggest gain in a single year: 2024/25: 118 in 2023/24 → 139, +21 pupils.
Biggest loss in a single year: 1993/94: 341 in 1983/84 → 250, -91 pupils.
Largest single-class increase: Junior Infants in 2024/25 (10 → 18, +8).
Largest single-class decrease: 2nd Class in 2021/22 (19 → 11, -8).
Largest cohort-step gain: 2nd → 3rd in 2024/25 (14 → 20, +6).
Largest cohort-step loss: 4th → 5th in 2021/22 (24 → 20, -4).
Overall: 392 (1974/75) → 141 (2025/26), -251.

Summary statistics (class-level data)

Min / max / mean enrolment per class across the available final by-standard years.

Class	Min	Max	Mean	Years
Junior Infants	10	21	14.7	6
Senior Infants	10	19	13.7	6
1st Class	11	14	12.3	6
2nd Class	11	19	14.8	6
3rd Class	13	20	16.7	6
4th Class	13	24	19.2	6
5th Class	16	21	18.5	6
6th Class	16	23	18.8	6
Total	118	392	240.4	43

Total enrolment over time

Total and gender trends use historical records where available. Class-level data starts in 2020/21.

Enrolment by gender over time

Enrolment by class over time

Cohort progression

Base cohort:

Track how each cohort (pupils who were in the same class in the same year) progresses through the school. Each step shows the count; the number between steps is the net change (pupils gained minus pupils lost).

Cohort 2020/21

JI 2020/21 11

-1

SI 2021/22 10

1st 2022/23 11

2nd 2023/24 14

3rd 2024/25 20

4th 2025/26 20

Cohort 2021/22

JI 2021/22 14

SI 2022/23 14

-1

1st 2023/24 13

2nd 2024/25 14

3rd 2025/26 14

Cohort 2022/23

JI 2022/23 14

-2

SI 2023/24 12

1st 2024/25 14

2nd 2025/26 17

Cohort 2023/24

JI 2023/24 10

SI 2024/25 14

-1

1st 2025/26 13

Cohort 2024/25

JI 2024/25 18

SI 2025/26 19

Cohort 2025/26

JI 2025/26 21

Raw data by year

Year	Female	Male	JI	SI	1st	2nd	3rd	4th	5th	6th	Total
1974/75	392	–	–	–	–	–	–	–	–	–	392
1975/76	–	–	–	–	–	–	–	–	–	–	385
1976/77	385	–	–	–	–	–	–	–	–	–	385
1977/78	392	–	–	–	–	–	–	–	–	–	392
1978/79	380	–	–	–	–	–	–	–	–	–	380
1979/80	367	–	–	–	–	–	–	–	–	–	367
1980/81	360	–	–	–	–	–	–	–	–	–	360
1981/82	360	–	–	–	–	–	–	–	–	–	360
1982/83	364	–	–	–	–	–	–	–	–	–	364
1983/84	341	–	–	–	–	–	–	–	–	–	341
1993/94	250	–	–	–	–	–	–	–	–	–	250
1994/95	248	–	–	–	–	–	–	–	–	–	248
1995/96	239	–	–	–	–	–	–	–	–	–	239
1996/97	244	–	–	–	–	–	–	–	–	–	244
1997/98	247	–	–	–	–	–	–	–	–	–	247
1998/99	222	–	–	–	–	–	–	–	–	–	222
1999/00	234	–	–	–	–	–	–	–	–	–	234
2000/01	223	–	–	–	–	–	–	–	–	–	223
2001/02	233	–	–	–	–	–	–	–	–	–	233
2002/03	225	–	–	–	–	–	–	–	–	–	225
2003/04	228	–	–	–	–	–	–	–	–	–	228
2004/05	215	–	–	–	–	–	–	–	–	–	215
2005/06	224	–	–	–	–	–	–	–	–	–	224
2006/07	226	–	–	–	–	–	–	–	–	–	226
2007/08	233	–	–	–	–	–	–	–	–	–	233
2008/09	239	–	–	–	–	–	–	–	–	–	239
2009/10	231	–	–	–	–	–	–	–	–	–	231
2010/11	233	–	–	–	–	–	–	–	–	–	233
2011/12	215	–	–	–	–	–	–	–	–	–	215
2012/13	219	–	–	–	–	–	–	–	–	–	219
2013/14	210	–	–	–	–	–	–	–	–	–	210
2014/15	191	–	–	–	–	–	–	–	–	–	191
2015/16	173	–	–	–	–	–	–	–	–	–	173
2016/17	159	–	–	–	–	–	–	–	–	–	159
2017/18	159	–	–	–	–	–	–	–	–	–	159
2018/19	150	–	–	–	–	–	–	–	–	–	150
2019/20	144	–	–	–	–	–	–	–	–	–	144
2020/21	143	–	11	13	11	19	20	24	17	23	143
2021/22	125	–	14	10	12	11	17	20	20	16	125
2022/23	132	–	14	14	11	14	13	19	20	22	132
2023/24	118	–	10	12	13	14	16	13	17	18	118
2024/25	139	–	18	14	14	14	20	19	16	18	139
2025/26	141	–	21	19	13	17	14	20	21	16	141