Playing around with NSIDC data … Extent and Difference in millions of sq km.

Most New Arctic Extent in any 30 day period for each year:

Year	Day1	Extent1	Day 30	Extent2	Difference	Percent
2007	286	5.30839	316	9.66878	4.36039	82.14
2008	273	4.93508	303	9.077	4.14192	83.93
1995	277	6.14383	307	10.13683	3.993	64.99
2011	279	5.29842	309	9.12387	3.82545	72.2
1990	270	6.17527	300	9.80574	3.63047	58.79
2005	281	6.23356	311	9.82469	3.59113	57.61
1993	277	7.33222	307	10.55187	3.21965	43.91
2009	280	5.83093	310	9.00812	3.17719	54.49
2010	280	5.9077	310	9.00754	3.09984	52.47
1999	265	6.16758	295	9.26104	3.09346	50.16
2006	275	6.0512	305	9.12123	3.07003	50.73
1991	271	6.51511	301	9.53251	3.0174	46.31
2002	269	6.08789	299	9.04441	2.95652	48.56
2003	276	6.5633	306	9.46735	2.90405	44.25
1982	272	7.63864	302	10.51943	2.88079	37.71
1989	272	7.20673	302	9.99355	2.78682	38.67
2000	272	6.57732	302	9.33106	2.75374	41.87
1997	280	7.39169	310	10.1265	2.73481	37
1996	329	10.85434	359	13.57832	2.72398	25.1
1979	312	10.27106	342	12.98561	2.71455	26.43
2004	280	7.02369	310	9.72652	2.70283	38.48
1983	299	9.47507	329	12.16115	2.68608	28.35
1980	321	11.2121	351	13.89477	2.68267	23.93
1985	276	7.51509	306	10.19703	2.68194	35.69
2001	289	8.20044	319	10.87187	2.67143	32.58
1984	312	10.06132	342	12.7188	2.65748	26.41
2012	262	3.51352	292	6.16765	2.65413	75.54
1998	267	6.5224	297	9.17577	2.65337	40.68
1981	325	11.25234	355	13.90002	2.64768	23.53
1988	311	10.44499	341	13.08941	2.64442	25.32
1994	281	8.05619	311	10.64024	2.58405	32.08
1992	310	10.4128	340	12.98672	2.57392	24.72
1987	300	9.46603	330	12.01156	2.54553	26.89
1986	267	7.53248	297	9.98248	2.45	32.53

2012 is way down so far because it has only been 44 days since minimum.