Table A4:

The Average Lengths of Systems after restricting the max-length during BART decoding.

Train	Test	Bart	T5	Pegasus
CNN/Daily Mail	CNN/Daily Mail	36.67	58.00	53.16
	XSum	36.61	45.59	44.26
	SP	38.36	63.43	45.05
	Reddit	38.52	44.92	52.35
	RCT	32.17	39.78	43.99
XSum	CNN/Daily Mail	21.69	23.06	19.11
	XSum	19.34	20.13	17.86
	SP	22.62	25.2	20.24
	Reddit	20.12	19.83	17.61
	RCT	22.72	20.13	19.32
SP	CNN/Daily Mail	69.51	83.39	95.33
	XSum	58.42	78.28	66.72
	SP	96.51	81.09	97.37
	Reddit	56.53	71.79	78.41
	RCT	35.33	46.69	66.12
Reddit	CNN/Daily Mail	54.06	84.04	78.96
	XSum	53.89	78.92	69.51
	SP	62.07	69.14	83.60
	Reddit	19.53	21.69	22.98
	RCT	44.15	46.41	92.51
RCT	CNN/Daily Mail	35.16	61.95	73.53
	XSum	28.92	62.61	48.73
	SP	28.71	45.38	49.48
	Reddit	24.60	60.40	62.59
	RCT	22.68	58.75	39.64