diff --git a/tests/data/gramtools/write_vcf_annotated_using_coverage_from_gramtools.out.vcf b/tests/data/gramtools/write_vcf_annotated_using_coverage_from_gramtools.out.vcf
index 7f45bfa..353feda 100644
--- a/tests/data/gramtools/write_vcf_annotated_using_coverage_from_gramtools.out.vcf
+++ b/tests/data/gramtools/write_vcf_annotated_using_coverage_from_gramtools.out.vcf
@@ -1,6 +1,6 @@
 ##fileformat=VCFv4.2
 ##source=minos, version 0.11.0
-##fileDate=2021-06-17
+##fileDate=2021-07-06
 ##FORMAT=<ID=ALLELE_DP,Number=R,Type=Float,Description="Mean read depth of ref and each allele">
 ##FORMAT=<ID=COV,Number=R,Type=Integer,Description="Number of reads on ref and alt alleles">
 ##FORMAT=<ID=COV_TOTAL,Number=1,Type=Integer,Description="Total reads mapped at this site, from gramtools">
@@ -8,10 +8,10 @@
 ##FORMAT=<ID=FRS,Number=1,Type=Float,Description="Fraction of reads that support the genotype call">
 ##FORMAT=<ID=GT,Number=1,Type=String,Description="Genotype">
 ##FORMAT=<ID=GT_CONF,Number=1,Type=Float,Description="Genotype confidence. Difference in log likelihood of most likely and next most likely genotype">
-##minosMeanReadDepth=5.5
-##minosReadDepthVariance=60.5
+##minosMeanReadDepth=4.333
+##minosReadDepthVariance=26.333
 ##contig=<ID=ref,length=10000>
 #CHROM	POS	ID	REF	ALT	QUAL	FILTER	INFO	FORMAT	sample_42
-ref	1	.	G	T	.	.	.	GT:DP:ALLELE_DP:FRS:COV_TOTAL:COV:GT_CONF	1/1:10:0,10:1.0:11:0,10:68.16
-ref	2	.	A	C,TA,G	.	.	.	GT:DP:ALLELE_DP:FRS:COV_TOTAL:COV:GT_CONF	3/3:3:0,1,2.5,3:0.6:10:1,0,3,5:13.45
+ref	1	.	G	T	.	.	.	GT:DP:ALLELE_DP:FRS:COV_TOTAL:COV:GT_CONF	1/1:10:0,10:1.0:11:0,10:68.28
+ref	2	.	A	C,TA,G	.	.	.	GT:DP:ALLELE_DP:FRS:COV_TOTAL:COV:GT_CONF	3/3:3:0,1,2.5,3:0.6:10:1,0,3,5:13.4
 ref	42	.	A	G	.	.	.	GT:DP:ALLELE_DP:FRS:COV_TOTAL:COV:GT_CONF	./.:.:0,0:.:0:0,0:0.0
diff --git a/tests/data/gramtools/write_vcf_annotated_using_coverage_from_gramtools.out.vcf.filter.vcf b/tests/data/gramtools/write_vcf_annotated_using_coverage_from_gramtools.out.vcf.filter.vcf
index ba340a7..46d8383 100644
--- a/tests/data/gramtools/write_vcf_annotated_using_coverage_from_gramtools.out.vcf.filter.vcf
+++ b/tests/data/gramtools/write_vcf_annotated_using_coverage_from_gramtools.out.vcf.filter.vcf
@@ -1,6 +1,6 @@
 ##fileformat=VCFv4.2
 ##source=minos, version 0.11.0
-##fileDate=2021-06-17
+##fileDate=2021-07-06
 ##FORMAT=<ID=ALLELE_DP,Number=R,Type=Float,Description="Mean read depth of ref and each allele">
 ##FORMAT=<ID=COV,Number=R,Type=Integer,Description="Number of reads on ref and alt alleles">
 ##FORMAT=<ID=COV_TOTAL,Number=1,Type=Integer,Description="Total reads mapped at this site, from gramtools">
@@ -8,10 +8,10 @@
 ##FORMAT=<ID=FRS,Number=1,Type=Float,Description="Fraction of reads that support the genotype call">
 ##FORMAT=<ID=GT,Number=1,Type=String,Description="Genotype">
 ##FORMAT=<ID=GT_CONF,Number=1,Type=Float,Description="Genotype confidence. Difference in log likelihood of most likely and next most likely genotype">
-##minosMeanReadDepth=5.5
-##minosReadDepthVariance=60.5
+##minosMeanReadDepth=4.333
+##minosReadDepthVariance=26.333
 ##contig=<ID=ref,length=10000>
 #CHROM	POS	ID	REF	ALT	QUAL	FILTER	INFO	FORMAT	sample_42
-ref	1	.	G	T	.	.	.	GT:DP:ALLELE_DP:FRS:COV_TOTAL:COV:GT_CONF	1/1:10:0,10:1.0:11:0,10:68.16
-ref	2	.	A	TA,G	.	.	.	GT:DP:ALLELE_DP:FRS:COV_TOTAL:COV:GT_CONF	2/2:3:0,2.5,3:0.6:10:1,3,5:13.45
+ref	1	.	G	T	.	.	.	GT:DP:ALLELE_DP:FRS:COV_TOTAL:COV:GT_CONF	1/1:10:0,10:1.0:11:0,10:68.28
+ref	2	.	A	TA,G	.	.	.	GT:DP:ALLELE_DP:FRS:COV_TOTAL:COV:GT_CONF	2/2:3:0,2.5,3:0.6:10:1,3,5:13.4
 ref	42	.	A	G	.	.	.	GT:DP:ALLELE_DP:FRS:COV_TOTAL:COV:GT_CONF	./.:.:0,0:.:0:0,0:0.0
diff --git a/tests/gramtools_test.py b/tests/gramtools_test.py
index b579843..ad35251 100644
--- a/tests/gramtools_test.py
+++ b/tests/gramtools_test.py
@@ -175,8 +175,8 @@ def test_load_gramtools_vcf_and_allele_coverage_files():
     expected_header, expected_vcf_records = vcf_file_read.vcf_file_to_list(vcf_file)
     assert got_vcf_header == expected_header
     assert got_vcf_records == expected_vcf_records
-    assert got_mean_depth == 11.000
-    assert got_depth_variance == 1.000
+    assert got_mean_depth == 6.5
+    assert got_depth_variance == 24.5
 
     # now test bad files cause error to be raised
     vcf_file = os.path.join(