Now estimate the Beta for GOLD using dat from jan-80/dec-85. Construct a 95% confidence interval for Beta. Has anything changed? Comment on supply and demand factors possibly alterating the Beta of gold

date	gold	market76	rkfree76
1-Jan-76	-0.10386	0.156	0.00369
1-Feb-76	0.05101	0.069	0.00369
1-Mar-76	0.01071	0.01	0.0039
1-Apr-76	-0.03494	-0.012	0.00383
1-May-76	-0.00771	0.005	0.00415
1-Jun-76	-0.00965	0.016	0.00431
1-Jul-76	-0.06505	-0.017	0.00416
1-Aug-76	-0.06703	-0.016	0.00389
1-Sep-76	0.04142	0.007	0.00412
1-Oct-76	0.01736	-0.029	0.00386
1-Nov-76	0.12637	0	0.00355
1-Dec-76	0.02306	0.111	0.00345
1-Jan-77	-0.01109	0.015	0.00372
1-Feb-77	0.02874	-0.012	0.00362
1-Mar-77	0.08703	0.008	0.00367
1-Apr-77	0.007	0.004	0.00359
1-May-77	-0.01637	-0.005	0.00394
1-Jun-77	-0.04394	0.07	0.004
1-Jul-77	0.04845	-0.002	0.00435
1-Aug-77	-0.01301	-0.023	0.00445
1-Sep-77	0.03048	0.008	0.00476
1-Oct-77	0.06156	-0.051	0.00473
1-Nov-77	-0.02912	0.083	0.0045
1-Dec-77	0.04163	0.039	0.00467
1-Jan-78	0.07788	-0.045	0.00487
1-Feb-78	0.02821	0.01	0.00494
1-Mar-78	0.03057	0.05	0.00526
1-Apr-78	-0.04548	0.063	0.00491
1-May-78	0.0045	0.067	0.00513
1-Jun-78	0.04295	0.007	0.00527
1-Jul-78	0.02814	0.071	0.00528
1-Aug-78	0.09005	0.079	0.00607
1-Sep-78	0.02977	0.002	0.00645
1-Oct-78	0.07194	-0.189	0.00685
1-Nov-78	-0.09443	0.084	0.00719
1-Dec-78	0.00941	0.015	0.0069
1-Jan-79	0.09336	0.058	0.00761
1-Feb-79	0.08042	0.011	0.00761
1-Mar-79	-0.01428	0.123	0.00769
1-Apr-79	-0.01333	0.026	0.00764
1-May-79	0.07745	0.014	0.00772
1-Jun-79	0.08434	0.075	0.00715
1-Jul-79	0.05802	-0.013	0.00728
1-Aug-79	0.02064	0.095	0.00789
1-Sep-79	0.18394	0.039	0.00802
1-Oct-79	0.09749	-0.097	0.00913
1-Nov-79	0.00163	0.116	0.00819
1-Dec-79	0.16912	0.086	0.00747
1-Jan-80	0.47437	0.124	0.00883
1-Feb-80	-0.01418	0.112	0.01073
1-Mar-80	-0.1682	-0.243	0.01181
1-Apr-80	-0.06696	0.08	0.00753
1-May-80	-0.0074	0.062	0.0063
1-Jun-80	0.16878	0.086	0.00503
1-Jul-80	0.07083	0.065	0.00602
1-Aug-80	-0.02459	0.025	0.00731
1-Sep-80	0.07699	0.015	0.0086
1-Oct-80	-0.02162	0.006	0.00895
1-Nov-80	-0.05855	0.092	0.01137
1-Dec-80	-0.04421	-0.056	0.00977
1-Jan-81	-0.06308	-0.014	0.01092
1-Feb-81	-0.1025	-0.009	0.01096
1-Mar-81	-0.003	0.067	0.01025
1-Apr-81	-0.00774	-0.008	0.01084
1-May-81	-0.03053	0.064	0.01255
1-Jun-81	-0.03966	-0.003	0.01128
1-Jul-81	-0.1126	-0.033	0.01154
1-Aug-81	0.00494	-0.031	0.01169
1-Sep-81	0.0808	-0.164	0.01054
1-Oct-81	-0.0143	0.062	0.01003
1-Nov-81	-0.05686	0.069	0.00816
1-Dec-81	-0.00855	-0.039	0.0074
1-Jan-82	-0.06156	-0.079	0.00949
1-Feb-82	-0.02619	-0.101	0.00946
1-Mar-82	-0.11714	-0.028	0.01067
1-Apr-82	0.06141	0.041	0.00972
1-May-82	-0.0461	0.003	0.00908
1-Jun-82	-0.05799	-0.078	0.00914
1-Jul-82	0.07975	-0.006	0.00714
1-Aug-82	0.07607	0.122	0.00503
1-Sep-82	0.19015	0.008	0.00563
1-Oct-82	-0.03079	0.136	0.0062
1-Nov-82	-0.01897	0.049	0.00614
1-Dec-82	0.07367	0.014	0.00648
1-Jan-83	0.07919	0.065	0.00646
1-Feb-83	0.02199	0.028	0.00599
1-Mar-83	-0.14419	0.043	0.00686
1-Apr-83	0.02952	0.097	0.00652
1-May-83	0.01291	0.08	0.00649
1-Jun-83	-0.05673	0.048	0.00673
1-Jul-83	0.0256	-0.017	0.00714
1-Aug-83	-0.01686	-0.034	0.00668
1-Sep-83	-0.01158	0	0.00702
1-Oct-83	-0.04246	-0.082	0.00678
1-Nov-83	-0.02957	0.066	0.00683
1-Dec-83	0.01488	-0.012	0.00693
1-Jan-84	-0.04322	-0.029	0.00712
1-Feb-84	0.04059	-0.03	0.00672
1-Mar-84	0.02159	0.003	0.00763
1-Apr-84	-0.03213	-0.003	0.00741
1-May-84	-0.01126	-0.058	0.00627
1-Jun-84	0.00103	0.005	0.00748
1-Jul-84	-0.08266	-0.058	0.00771
1-Aug-84	0.0036	0.146	0.00852
1-Sep-84	-0.01942	0	0.0083
1-Oct-84	-0.00217	-0.035	0.00688
1-Nov-84	0.00285	-0.019	0.00602
1-Dec-84	-0.06479	-0.001	0.00612
1-Jan-85	-0.06265	0.097	0.00606
1-Feb-85	0.0172	0.012	0.00586
1-Mar-85	-0.044	0.008	0.0065
1-Apr-85	0.13447	-0.01	0.00601
1-May-85	-0.02165	0.019	0.00512
1-Jun-85	-0.01393	-0.003	0.00536
1-Jul-85	-0.00816	0.012	0.00562
1-Aug-85	0.03275	0.005	0.00545
1-Sep-85	-0.0144	-0.055	0.00571
1-Oct-85	0.01663	0.026	0.00577
1-Nov-85	-0.00413	0.059	0.0054
1-Dec-85	-0.02318	0.013	0.00479
.