Chủ	Hòa	Khách	Chủ%	HH%	Khách%	Hoàn vốn%	Tiêu chuẩn Kelly			Mới nhất
2.32	3.40	2.29	37.10	25.31	37.59	86.07	0.70	1.01	0.92	04/25 11:18
3.80	3.20	1.79	23.20	27.55	49.25	88.16	0.70	1.01	0.92	04/25 11:18
2.75	3.25	2.24	32.53	27.53	39.94	89.46	0.83	0.97	0.90	04/25 11:13
4.50	3.50	1.64	19.88	25.56	54.55	89.47	0.83	0.97	0.90	04/25 11:13
2.75	3.00	2.55	33.39	30.61	36.01	91.82	0.83	0.89	1.03	04/25 10:54
3.35	3.00	2.17	27.32	30.51	42.17	91.52	0.83	0.89	1.03	04/25 10:54
2.63	3.30	2.45	34.84	27.76	37.40	91.62	0.79	0.98	0.98	04/25 11:21
3.90	3.60	1.80	23.53	25.49	50.98	91.76	0.79	0.98	0.98	04/25 11:21
2.87	3.25	2.15	31.08	27.44	41.48	89.19	0.86	0.97	0.86	04/25 11:13
3.70	3.40	1.80	24.13	26.26	49.61	89.29	0.86	0.97	0.86	04/25 11:13
2.80	3.25	2.20	31.91	27.49	40.61	89.34	0.84	0.97	0.88	04/25 10:44
2.90	3.25	2.15	30.85	27.53	41.62	89.47	0.84	0.97	0.88	04/25 10:44
2.50	3.65	2.45	36.96	25.32	37.72	92.41	0.75	1.09	0.98	04/25 11:11
3.70	3.20	1.95	24.67	28.52	46.81	91.27	0.75	1.09	0.98	04/25 11:11
2.80	3.25	2.38	32.92	28.36	38.73	92.17	0.84	0.97	0.96	04/25 11:14
4.00	3.60	1.80	23.08	25.64	51.28	92.31	0.84	0.97	0.96	04/25 11:14
2.74	3.27	2.34	33.24	27.85	38.92	91.06	0.82	0.97	0.94	04/25 11:14
4.47	3.09	1.84	20.51	29.67	49.82	91.67	0.82	0.97	0.94	04/25 11:14
2.40	3.60	2.40	37.50	25.00	37.50	90.00	0.72	1.07	0.96	04/25 11:15
4.50	3.10	1.80	20.20	29.32	50.49	90.88	0.72	1.07	0.96	04/25 11:15
2.88	3.25	2.20	31.30	27.73	40.97	90.13	0.87	0.97	0.88	04/22 12:14
2.88	3.25	2.20	31.30	27.73	40.97	90.13	0.87	0.97	0.88	04/22 12:14
2.87	3.25	2.15	31.08	27.44	41.48	89.19	0.86	0.97	0.86	04/25 10:44
2.90	3.25	2.10	30.55	27.26	42.19	88.60	0.86	0.97	0.86	04/25 10:44
2.75	3.16	2.16	31.81	27.69	40.50	87.48	0.83	0.94	0.87	04/25 11:11
3.68	3.33	1.82	24.23	26.78	48.99	89.17	0.83	0.94	0.87	04/25 11:11
2.70	3.40	2.20	33.10	26.28	40.62	89.36	0.81	1.01	0.88	04/25 08:59
3.10	3.20	2.20	29.60	28.68	41.72	91.77	0.81	1.01	0.88	04/25 08:59
2.75	3.25	2.24	32.53	27.53	39.94	89.46	0.83	0.97	0.90	04/25 11:13
4.50	3.50	1.64	19.88	25.56	54.55	89.47	0.83	0.97	0.90	04/25 11:13
2.70	3.35	2.07	32.15	25.91	41.94	86.81	0.81	1.00	0.83	04/25 10:56
3.45	3.45	1.75	25.18	25.18	49.64	86.87	0.81	1.00	0.83	04/25 10:56
2.80	3.25	2.37	32.86	28.31	38.83	92.02	0.84	0.97	0.95	04/25 10:44
3.10	3.30	2.15	29.57	27.78	42.64	91.68	0.84	0.97	0.95	04/25 10:44
2.62	3.30	2.45	34.92	27.73	37.35	91.50	0.79	0.98	0.98	04/25 10:44
3.10	3.40	2.10	29.52	26.91	43.57	91.50	0.79	0.98	0.98	04/25 10:44
2.56	3.40	2.40	35.47	26.70	37.83	90.79	0.77	1.01	0.96	04/25 11:21
3.66	3.44	1.86	24.80	26.39	48.81	90.78	0.77	1.01	0.96	04/25 11:21
2.58	3.50	2.40	35.56	26.21	38.23	91.74	0.78	1.04	0.96	04/25 10:44
3.25	3.20	2.10	28.06	28.50	43.43	91.21	0.78	1.04	0.96	04/25 10:44
2.60	3.60	2.30	35.06	25.32	39.63	91.14	0.78	1.07	0.92	04/25 10:09
2.80	3.70	2.15	32.69	24.74	42.57	91.53	0.78	1.07	0.92	04/25 10:09
2.60	3.40	2.35	34.83	26.63	38.54	90.56	0.78	1.01	0.94	04/24 19:54
3.00	2.70	2.50	30.20	33.56	36.24	90.60	0.78	1.01	0.94	04/24 19:54
2.60	3.35	2.20	33.81	26.24	39.95	87.90	0.78	1.00	0.88	04/25 10:44
3.35	3.10	2.10	27.20	29.40	43.40	91.13	0.78	1.00	0.88	04/25 10:44
2.71	3.26	2.30	33.23	27.62	39.15	90.05	0.81	0.97	0.92	04/25 10:55
3.24	2.96	2.16	27.82	30.45	41.73	90.14	0.81	0.97	0.92	04/25 10:55
2.71	3.26	2.30	33.23	27.62	39.15	90.05	0.81	0.97	0.92	04/25 10:44
3.22	2.99	2.15	27.98	30.13	41.90	90.08	0.81	0.97	0.92	04/25 10:44
2.87	3.06	2.52	32.50	30.48	37.02	93.28	0.86	0.91	1.01	04/25 10:55
3.32	3.08	2.29	28.35	30.56	41.10	94.11	0.86	0.91	1.01	04/25 10:55
2.50	3.40	2.34	35.67	26.23	38.11	89.17	0.75	1.01	0.94	04/25 10:44
3.20	3.15	2.08	28.13	28.58	43.28	90.03	0.75	1.01	0.94	04/25 10:44
2.75	3.35	2.40	33.71	27.67	38.62	92.69	0.83	1.00	0.96	04/25 10:55
3.15	3.35	2.15	29.36	27.61	43.02	92.50	0.83	1.00	0.96	04/25 10:55
2.52	3.51	2.23	35.11	25.21	39.68	88.48	0.76	1.04	0.90	04/25 10:54
3.29	2.95	2.19	27.64	30.83	41.53	90.95	0.76	1.04	0.90	04/25 10:54
2.60	3.35	2.20	33.81	26.24	39.95	87.90	0.78	1.00	0.88	04/25 11:21
4.10	3.25	1.82	22.15	27.95	49.90	90.82	0.78	1.00	0.88	04/25 11:21
2.61	3.35	2.27	34.14	26.60	39.26	89.11	0.78	1.00	0.91	04/25 10:09
3.10	3.15	2.13	29.07	28.61	42.31	90.13	0.78	1.00	0.91	04/25 10:09
2.62	3.30	2.45	34.92	27.73	37.35	91.50	0.79	0.98	0.98	04/25 10:44
3.10	3.40	2.10	29.52	26.91	43.57	91.50	0.79	0.98	0.98	04/25 10:44
2.76	3.26	2.32	32.94	27.88	39.18	90.90	0.83	0.97	0.93	04/25 11:21
4.39	3.08	1.83	20.73	29.55	49.73	91.00	0.83	0.97	0.93	04/25 11:21
2.44	3.60	2.41	37.17	25.19	37.63	90.70	0.73	1.07	0.97	04/25 10:54
3.30	3.25	2.13	28.05	28.48	43.46	92.57	0.73	1.07	0.97	04/25 10:54
2.54	3.55	2.25	35.16	25.15	39.69	89.30	0.76	1.06	0.90	04/25 10:54
3.33	2.98	2.20	27.54	30.77	41.69	91.71	0.76	1.06	0.90	04/25 10:54
2.85	3.25	2.17	31.35	27.49	41.17	89.33	0.86	0.97	0.87	04/22 12:14
2.85	3.25	2.17	31.35	27.49	41.17	89.33	0.86	0.97	0.87	04/22 12:14
2.46	3.65	2.44	37.28	25.13	37.59	91.72	0.74	1.09	0.98	04/25 10:54
3.25	3.25	2.12	28.30	28.30	43.39	91.99	0.74	1.09	0.98	04/25 10:54
2.70	3.50	2.35	34.24	26.42	39.34	92.45	0.81	1.04	0.94	04/25 10:44
3.30	3.25	2.14	28.11	28.54	43.35	92.76	0.81	1.04	0.94	04/25 10:44
2.76	3.26	2.32	32.94	27.88	39.18	90.90	0.83	0.97	0.93	04/25 10:44
3.29	2.99	2.17	27.65	30.43	41.92	90.97	0.83	0.97	0.93	04/25 10:44
2.66	3.50	2.33	34.46	26.19	39.34	91.67	0.80	1.04	0.94	04/25 08:59
3.25	3.10	2.16	28.15	29.51	42.35	91.47	0.80	1.04	0.94	04/25 08:59
2.73	3.52	2.34	33.99	26.36	39.65	92.79	0.82	1.05	0.94	04/25 10:44
3.31	3.28	2.16	28.24	28.49	43.27	93.46	0.82	1.05	0.94	04/25 10:44
2.67	2.95	2.52	33.73	30.53	35.74	90.06	0.80	0.88	1.01	04/23 23:07
2.67	2.95	2.52	33.73	30.53	35.74	90.06	0.80	0.88	1.01	04/23 23:07
3.00	3.25	2.26	30.76	28.40	40.84	92.29	0.90	0.97	0.91	04/25 10:55
3.30	3.25	2.13	28.05	28.48	43.46	92.57	0.90	0.97	0.91	04/25 10:55
2.70	3.40	2.30	33.69	26.76	39.55	90.97	0.81	1.01	0.92	04/25 10:44
3.15	3.30	2.10	28.95	27.63	43.42	91.18	0.81	1.01	0.92	04/25 10:44
2.57	3.58	2.27	35.09	25.19	39.72	90.17	0.77	1.06	0.91	04/25 10:55
3.36	3.01	2.22	27.55	30.75	41.70	92.57	0.77	1.06	0.91	04/25 10:55
2.76	3.26	2.32	32.94	27.88	39.18	90.90	0.83	0.97	0.93	04/25 03:09
3.19	2.93	2.25	28.52	31.05	40.43	90.97	0.83	0.97	0.93	04/25 03:09
2.76	3.26	2.32	32.94	27.88	39.18	90.90	0.83	0.97	0.93	04/25 08:49
3.21	2.94	2.23	28.32	30.92	40.76	90.90	0.83	0.97	0.93	04/25 08:49
2.76	3.26	2.32	32.94	27.88	39.18	90.90	0.83	0.97	0.93	04/25 10:44
3.29	2.99	2.17	27.65	30.43	41.92	90.97	0.83	0.97	0.93	04/25 10:44
2.52	3.51	2.23	35.11	25.21	39.68	88.48	0.76	1.04	0.90	04/25 10:10
3.23	3.00	2.19	28.16	30.32	41.53	90.95	0.76	1.04	0.90	04/25 10:10
2.47	3.65	2.43	37.13	25.13	37.74	91.71	0.74	1.09	0.98	04/25 10:54
3.35	3.30	2.09	27.64	28.06	44.30	92.59	0.74	1.09	0.98	04/25 10:54
2.70	3.40	2.35	33.98	26.98	39.04	91.74	0.81	1.01	0.94	04/25 10:54
3.35	3.00	2.17	27.32	30.51	42.17	91.52	0.81	1.01	0.94	04/25 10:54
2.60	3.64	2.29	35.09	25.07	39.84	91.24	0.78	1.08	0.92	04/25 10:54
3.41	3.05	2.25	27.52	30.77	41.71	93.85	0.78	1.08	0.92	04/25 10:54
2.75	3.25	2.35	33.15	28.05	38.80	91.17	0.83	0.97	0.94	04/25 10:55
3.35	3.00	2.21	27.53	30.74	41.73	92.22	0.83	0.97	0.94	04/25 10:55
2.52	3.51	2.23	35.11	25.21	39.68	88.48	0.76	1.04	0.90	04/25 10:10
3.23	3.00	2.19	28.16	30.32	41.53	90.95	0.76	1.04	0.90	04/25 10:10
2.77	3.27	2.37	33.16	28.09	38.75	91.85	0.83	0.97	0.95	04/25 10:54
3.34	2.99	2.20	27.51	30.73	41.76	91.88	0.83	0.97	0.95	04/25 10:54
2.76	3.26	2.32	32.94	27.88	39.18	90.90	0.83	0.97	0.93	04/25 10:55
3.31	2.96	2.18	27.50	30.75	41.75	91.02	0.83	0.97	0.93	04/25 10:55
2.76	3.26	2.32	32.94	27.88	39.18	90.90	0.83	0.97	0.93	04/25 08:49
3.21	2.94	2.23	28.32	30.92	40.76	90.90	0.83	0.97	0.93	04/25 08:49
2.70	3.40	2.35	33.98	26.98	39.04	91.74	0.81	1.01	0.94	04/25 08:49
3.20	3.05	2.20	28.54	29.94	41.51	91.33	0.81	1.01	0.94	04/25 08:49
2.76	3.26	2.32	32.94	27.88	39.18	90.90	0.83	0.97	0.93	04/25 08:49
3.21	2.94	2.23	28.32	30.92	40.76	90.90	0.83	0.97	0.93	04/25 08:49
2.52	3.51	2.23	35.11	25.21	39.68	88.48	0.76	1.04	0.90	04/25 10:55
3.29	2.95	2.19	27.64	30.83	41.53	90.95	0.76	1.04	0.90	04/25 10:55
2.52	3.51	2.23	35.11	25.21	39.68	88.48	0.76	1.04	0.90	04/24 23:40
3.21	2.93	2.24	28.34	31.05	40.61	90.97	0.76	1.04	0.90	04/24 23:40
2.52	3.51	2.23	35.11	25.21	39.68	88.48	0.76	1.04	0.90	04/24 23:40
3.21	2.93	2.24	28.34	31.05	40.61	90.97	0.76	1.04	0.90	04/24 23:40
2.85	3.05	2.25	31.24	29.19	39.57	89.03	0.86	0.91	0.90	04/25 10:44
3.20	3.20	2.10	28.38	28.38	43.24	90.81	0.86	0.91	0.90	04/25 10:44
2.70	3.25	2.51	34.41	28.58	37.01	92.90	0.81	0.97	1.01	04/25 10:54
3.38	3.34	2.11	27.67	28.00	44.33	93.53	0.81	0.97	1.01	04/25 10:54
2.50	3.40	2.34	35.67	26.23	38.11	89.17	0.75	1.01	0.94	04/25 10:44
3.20	3.15	2.08	28.13	28.58	43.28	90.03	0.75	1.01	0.94	04/25 10:44
2.50	3.40	2.34	35.67	26.23	38.11	89.17	0.75	1.01	0.94	04/25 10:44
3.20	3.15	2.08	28.13	28.58	43.28	90.03	0.75	1.01	0.94	04/25 10:44
2.66	3.33	2.28	33.72	26.94	39.34	89.70	0.80	0.99	0.92	04/25 08:59
3.25	3.00	2.14	27.76	30.08	42.16	90.23	0.80	0.99	0.92	04/25 08:59
2.66	3.50	2.33	34.46	26.19	39.34	91.67	0.80	1.04	0.94	04/25 08:59
3.25	3.10	2.16	28.15	29.51	42.35	91.47	0.80	1.04	0.94	04/25 08:59
2.62	3.60	2.32	35.00	25.47	39.53	91.70	0.79	1.07	0.93	04/25 10:44
3.55	2.67	2.32	25.91	34.45	39.64	91.97	0.79	1.07	0.93	04/25 10:44
3.10	2.90	2.20	28.75	30.73	40.51	89.13	0.93	0.86	0.88	04/25 08:59
3.25	2.90	2.14	27.48	30.79	41.73	89.30	0.93	0.86	0.88	04/25 08:59
2.70	3.40	2.35	33.98	26.98	39.04	91.74	0.81	1.01	0.94	04/25 10:44
3.35	3.05	2.15	27.35	30.04	42.61	91.62	0.81	1.01	0.94	04/25 10:44
2.50	3.40	2.35	35.73	26.27	38.01	89.31	0.75	1.01	0.94	04/25 08:59
3.10	3.20	2.20	29.60	28.68	41.72	91.77	0.75	1.01	0.94	04/25 08:59
2.90	3.10	2.25	31.01	29.01	39.97	89.94	0.87	0.92	0.90	04/25 10:44
3.20	3.15	2.10	28.25	28.70	43.05	90.40	0.87	0.92	0.90	04/25 10:44
2.40	3.55	2.35	37.07	25.06	37.86	88.98	0.72	1.06	0.94	04/25 08:59
3.10	3.20	2.20	29.60	28.68	41.72	91.77	0.72	1.06	0.94	04/25 08:59
2.50	3.40	2.35	35.73	26.27	38.01	89.31	0.75	1.01	0.94	04/25 10:44
3.20	3.20	2.10	28.38	28.38	43.24	90.81	0.75	1.01	0.94	04/25 10:44
2.88	3.25	2.20	31.30	27.73	40.97	90.13	0.87	0.97	0.88	04/22 14:52
2.88	3.25	2.20	31.30	27.73	40.97	90.13	0.87	0.97	0.88	04/22 14:52
2.69	3.28	2.31	33.51	27.48	39.02	90.13	0.81	0.98	0.93	04/25 10:55
3.31	2.96	2.18	27.50	30.75	41.75	91.02	0.81	0.98	0.93	04/25 10:55
2.40	3.55	2.35	37.07	25.06	37.86	88.98	0.72	1.06	0.94	04/25 10:55
3.30	3.20	2.10	27.76	28.62	43.62	91.60	0.72	1.06	0.94	04/25 10:55
2.40	3.55	2.35	37.07	25.06	37.86	88.98	0.72	1.06	0.94	04/24 16:25
2.85	3.10	2.25	31.39	28.86	39.76	89.45	0.72	1.06	0.94	04/24 16:25
3.25	2.90	2.28	28.20	31.60	40.20	91.65	0.98	0.86	0.92	04/25 10:55
3.40	3.00	2.16	26.97	30.57	42.46	91.71	0.98	0.86	0.92	04/25 10:55
3.25	2.90	2.28	28.20	31.60	40.20	91.65	0.98	0.86	0.92	04/25 08:49
3.25	3.10	2.16	28.15	29.51	42.35	91.47	0.98	0.86	0.92	04/25 08:49
2.76	3.26	2.32	32.94	27.88	39.18	90.90	0.83	0.97	0.93	04/25 08:49
3.21	2.94	2.23	28.32	30.92	40.76	90.90	0.83	0.97	0.93	04/25 08:49
3.21	2.98	2.21	28.33	30.52	41.15	90.94	0.97	0.89	0.89	04/25 10:54
3.29	2.95	2.19	27.64	30.83	41.53	90.95	0.97	0.89	0.89	04/25 10:54
2.52	3.51	2.23	35.11	25.21	39.68	88.48	0.76	1.04	0.90	04/24 23:40
3.21	2.93	2.24	28.34	31.05	40.61	90.97	0.76	1.04	0.90	04/24 23:40
2.68	3.35	2.34	33.95	27.16	38.89	90.99	0.81	1.00	0.94	04/24 15:15
2.96	3.00	2.32	30.65	30.24	39.11	90.73	0.81	1.00	0.94	04/24 15:15
2.68	3.35	2.34	33.95	27.16	38.89	90.99	0.81	1.00	0.94	04/24 15:15
2.96	3.00	2.32	30.65	30.24	39.11	90.73	0.81	1.00	0.94	04/24 15:15
2.68	3.35	2.34	33.95	27.16	38.89	90.99	0.81	1.00	0.94	04/24 15:15
2.96	3.00	2.32	30.65	30.24	39.11	90.73	0.81	1.00	0.94	04/24 15:15
2.70	3.00	2.60	34.03	30.63	35.34	91.88	0.81	0.89	1.05	04/25 10:09
3.30	3.00	2.25	28.04	30.84	41.12	92.52	0.81	0.89	1.05	04/25 10:09
2.76	3.26	2.32	32.94	27.88	39.18	90.90	0.83	0.97	0.93	04/25 08:49
3.21	2.94	2.23	28.32	30.92	40.76	90.90	0.83	0.97	0.93	04/25 08:49
2.76	3.26	2.32	32.94	27.88	39.18	90.90	0.83	0.97	0.93	04/25 08:49
3.21	2.94	2.23	28.32	30.92	40.76	90.90	0.83	0.97	0.93	04/25 08:49
2.68	3.35	2.34	33.95	27.16	38.89	90.99	0.81	1.00	0.94	04/24 15:15
2.96	3.00	2.32	30.65	30.24	39.11	90.73	0.81	1.00	0.94	04/24 15:15

	Nhà cái
	10BET
	10BET
	12bet
	12bet
	Fonbet
	Fonbet
	Vcbet
	Vcbet
	Ladbrokes
	Ladbrokes
	Coral
	Coral
	Interwetten
	Interwetten
	William Hill
	William Hill
	Pinnacle
	Pinnacle
	Bet 365
	Bet 365
	Unibet
	Unibet
	Sportingbet
	Sportingbet
	Sbobet
	Sbobet
	Betway
	Betway
	Mansion88
	Mansion88
	Crown
	Crown
	888Sport
	888Sport
	PariMatch
	PariMatch
	Wewbet
	Wewbet
	Betsson
	Betsson
	Germania Sport
	Germania Sport
	novibet
	novibet
	1Bet
	1Bet
	Marathon
	Marathon
	Marathonbet
	Marathonbet
	FavBet
	FavBet
	TonyBet
	TonyBet
	Mozzart
	Mozzart
	VBet
	VBet
	18Bet
	18Bet
	Luckia.es
	Luckia.es
	BetVictor
	BetVictor
	1xBet
	1xBet
	WinlineBet
	WinlineBet
	Betboro
	Betboro
	Leovegas
	Leovegas
	Liga Stavok
	Liga Stavok
	Bet9ja
	Bet9ja
	22Bet
	22Bet
	FEZbet
	FEZbet
	GGBET
	GGBET
	Marathonbet.ru
	Marathonbet.ru
	Winline.ru
	Winline.ru
	LSbet
	LSbet
	Bet Sensation
	Bet Sensation
	Paripesa
	Paripesa
	Melbet
	Melbet
	Megapari
	Megapari
	N1 BET
	N1 BET
	BetBoom.ru
	BetBoom.ru
	prism
	prism
	Vbet.CAN
	Vbet.CAN
	Pin-Up
	Pin-Up
	Betibet
	Betibet
	BetBoom
	BetBoom
	1xBit
	1xBit
	spinbetter
	spinbetter
	Фонбет
	Фонбет
	888Starz
	888Starz
	N1BET.it
	N1BET.it
	N1BET.de
	N1BET.de
	N1BET.se
	N1BET.se
	Stake
	Stake
	GGBet.ua
	GGBet.ua
	20Bet
	20Bet
	Ivibet
	Ivibet
	Campobet
	Campobet
	ToonieBet
	ToonieBet
	Betano
	Betano
	All British Casino
	All British Casino
	Mostbet
	Mostbet
	Mystake
	Mystake
	Admiralbet IT
	Admiralbet IT
	Jackbit
	Jackbit
	Goldenbet
	Goldenbet
	BetUK
	BetUK
	BetAndYou
	BetAndYou
	Cosmobet
	Cosmobet
	Velobet
	Velobet
	Lunubet
	Lunubet
	Boomerang-bet
	Boomerang-bet
	Fairpari
	Fairpari
	Rocketplay
	Rocketplay
	Winspirit
	Winspirit
	Oscarspin
	Oscarspin
	Goldzino
	Goldzino
	Igobet
	Igobet
	Winbay
	Winbay
	Betlabel ES
	Betlabel ES
	Paripesa Europe
	Paripesa Europe
	Rainbe*
	Rainbe*


Tỷ lệ ban đầu cao nhất
Tỷ lệ cao nhất
Tỷ lệ ban đầu thấp nhất
Tỷ lệ thấp nhất
Tỷ lệ ban đầu trung bình
Tỷ lệ trung bình

Tỷ lệ thay đổi
0.00	0.00	0.00	(Sớm)

Bedford Town VS Scarborough ngày 25-04-2026 - Tỷ lệ kèo