This file presents quarterly data from the first quarter of 1962 through the second quarter of 2021 on Real GDP (RGDP), the unemployment rate (UR), the Consumer Price Index (CPI), and the M1 money supply (M1). The trend variable (TREND) is also included. 1. Suppose we conduct a regression with RGDP as the dependent variable and TREND, UR, CPI and M1 as the explanatory variables. We wish to test this model for heteroscedasticity. Use the White's test and the modified White's test at the 0.01 level to determine whether heteroscedasticity exists. If heteroscedasticity exists, what variables might be causing it based on your regression results? You do not need to try and correct for heteroscedasticity in this problem.

RGDP:		Real GDP in 2012 dollars (millions of dollars)
UR:		Civilian Unemployment Rate (percent)
CPI:		Consumer Price Index
M1:		M1 Money Supply (millions of dollars)
TREND:		Trend (observation number)
YEAR	QTR	RGDP	TREND	UR	CPI	M1
1962	1	3192.380	1	5.100	29.043	140.533
1962	2	3194.653	2	5.267	29.193	141.533
1962	3	3203.759	3	5.600	29.370	140.267
1962	4	3275.757	4	5.133	29.397	139.900
1963	1	3258.088	5	5.233	29.573	139.600
1963	2	3274.029	6	5.533	29.590	140.900
1963	3	3232.009	7	6.267	29.780	140.833
1963	4	3253.826	8	6.800	29.840	141.533
1964	1	3309.059	9	7.000	29.830	142.567
1964	2	3372.581	10	6.767	29.947	143.400
1964	3	3438.721	11	6.200	29.990	144.700
1964	4	3500.054	12	5.633	30.107	145.633
1965	1	3531.683	13	5.533	30.220	146.600
1965	2	3575.070	14	5.567	30.307	146.467
1965	3	3586.827	15	5.533	30.380	147.267
1965	4	3625.981	16	5.767	30.477	148.800
1966	1	3666.669	17	5.733	30.533	150.167
1966	2	3747.278	18	5.500	30.720	151.700
1966	3	3771.845	19	5.567	30.803	153.167
1966	4	3851.366	20	5.467	30.930	154.167
1967	1	3893.296	21	5.200	30.980	155.233
1967	2	3954.121	22	5.000	31.050	157.767
1967	3	3966.335	23	4.967	31.193	159.833
1967	4	4062.311	24	4.900	31.290	161.033
1968	1	4113.629	25	4.667	31.490	161.967
1968	2	4205.086	26	4.367	31.583	163.833
1968	3	4301.973	27	4.100	31.750	166.833
1968	4	4406.693	28	3.867	32.047	169.733
1969	1	4421.747	29	3.833	32.337	171.567
1969	2	4459.195	30	3.767	32.617	171.033
1969	3	4495.777	31	3.700	32.883	171.533
1969	4	4535.591	32	3.833	32.967	173.233
1970	1	4538.370	33	3.833	33.167	175.633
1970	2	4581.309	34	3.800	33.500	179.500
1970	3	4615.853	35	3.900	33.867	182.433
1970	4	4709.993	36	3.733	34.200	184.833
1971	1	4788.688	37	3.567	34.533	188.000
1971	2	4825.799	38	3.533	35.000	191.667
1971	3	4844.779	39	3.400	35.433	195.800
1971	4	4920.605	40	3.400	35.867	199.333
1972	1	4935.564	41	3.433	36.433	200.933
1972	2	4968.164	42	3.567	36.933	201.833
1972	3	4943.935	43	3.567	37.500	203.467
1972	4	4936.594	44	4.167	38.100	205.633
1973	1	4943.600	45	4.767	38.633	207.167
1973	2	4989.159	46	5.167	39.033	209.900
1973	3	4935.693	47	5.833	39.600	213.667
1973	4	5069.746	48	5.933	39.933	217.233
1974	1	5097.179	49	5.900	40.300	221.833
1974	2	5139.128	50	6.033	40.700	225.667
1974	3	5151.245	51	5.933	41.000	227.767
1974	4	5245.974	52	5.767	41.333	232.233
1975	1	5365.045	53	5.700	41.600	236.033
1975	2	5415.712	54	5.567	41.933	240.967
1975	3	5506.396	55	5.367	42.367	246.867
1975	4	5642.669	56	4.933	43.033	251.800
1976	1	5704.098	57	4.933	43.933	254.767
1976	2	5674.100	58	4.800	44.800	257.700
1976	3	5727.960	59	4.767	45.933	260.967
1976	4	5678.713	60	5.133	47.300	265.267
1977	1	5692.210	61	5.200	48.567	267.767
1977	2	5638.411	62	5.633	49.933	270.133
1977	3	5616.526	63	6.600	51.467	273.400
1977	4	5548.156	64	8.267	52.567	275.100
1978	1	5587.800	65	8.867	53.200	279.267
1978	2	5683.444	66	8.467	54.267	284.500
1978	3	5759.972	67	8.300	55.267	286.433
1978	4	5889.500	68	7.733	55.900	290.633
1979	1	5932.711	69	7.567	56.400	295.600
1979	2	5965.265	70	7.733	57.300	298.600
1979	3	6008.504	71	7.767	58.133	303.933
1979	4	6079.494	72	7.500	59.200	311.233
1980	1	6197.686	73	7.133	60.233	317.333
1980	2	6309.514	74	6.900	61.067	322.333
1980	3	6309.652	75	6.667	61.967	328.633
1980	4	6329.791	76	6.333	63.033	335.567
1981	1	6574.390	77	6.000	64.467	343.900
1981	2	6640.497	78	6.033	65.967	349.800
1981	3	6729.755	79	5.900	67.500	355.333
1981	4	6741.854	80	5.867	69.200	360.333
1982	1	6749.063	81	5.700	71.400	370.333
1982	2	6799.200	82	5.867	73.700	378.433
1982	3	6816.203	83	5.967	76.033	381.133
1982	4	6837.641	84	6.300	79.033	388.100
1983	1	6696.753	85	7.333	81.700	385.900
1983	2	6688.794	86	7.667	83.233	399.333
1983	3	6813.535	87	7.400	85.567	409.400
1983	4	6947.042	88	7.433	87.933	415.033
1984	1	6895.559	89	7.400	89.767	425.767
1984	2	6978.135	90	7.400	92.267	426.933
1984	3	6902.105	91	8.233	93.767	432.133
1984	4	6794.878	92	8.833	94.600	442.433
1985	1	6825.876	93	9.433	95.967	447.100
1985	2	6799.781	94	9.900	97.633	452.100
1985	3	6802.497	95	10.667	97.933	470.267
1985	4	6892.144	96	10.367	98.000	484.033
1986	1	7048.982	97	10.133	99.133	499.067
1986	2	7189.896	98	9.367	100.100	510.367
1986	3	7339.893	99	8.533	101.100	519.200
1986	4	7483.371	100	7.867	102.533	528.000
1987	1	7612.668	101	7.433	103.500	537.300
1987	2	7686.059	102	7.433	104.400	541.667
1987	3	7749.151	103	7.300	105.300	547.600
1987	4	7824.247	104	7.233	106.267	562.400
1988	1	7893.136	105	7.300	107.233	575.933
1988	2	8013.674	106	7.200	107.900	596.200
1988	3	8073.239	107	7.033	109.000	613.267
1988	4	8148.603	108	7.033	109.567	626.700
1989	1	8185.303	109	7.167	109.033	651.200
1989	2	8263.639	110	6.967	109.700	678.800
1989	3	8308.021	111	6.833	110.467	708.333
1989	4	8369.930	112	6.600	111.800	731.567
1990	1	8460.233	113	6.267	113.067	744.300
1990	2	8533.635	114	6.000	114.267	745.167
1990	3	8680.162	115	5.833	115.333	753.200
1990	4	8725.006	116	5.700	116.233	758.567
1991	1	8839.641	117	5.467	117.567	772.700
1991	2	8891.435	118	5.467	119.000	782.800
1991	3	9009.913	119	5.333	120.300	784.967
1991	4	9101.508	120	5.200	121.667	784.167
1992	1	9170.977	121	5.233	123.633	775.900
1992	2	9238.923	122	5.233	124.600	779.400
1992	3	9257.128	123	5.367	125.867	789.133
1992	4	9358.289	124	5.300	128.033	798.333
1993	1	9392.251	125	5.333	129.300	806.367
1993	2	9398.499	126	5.700	131.533	815.333
1993	3	9312.937	127	6.133	133.767	822.233
1993	4	9269.367	128	6.600	134.767	832.833
1994	1	9341.642	129	6.833	135.567	849.533
1994	2	9388.845	130	6.867	136.600	866.033
1994	3	9421.565	131	7.100	137.733	887.533
1994	4	9534.346	132	7.367	138.667	924.100
1995	1	9637.732	133	7.600	139.733	949.567
1995	2	9732.979	134	7.633	140.800	975.000
1995	3	9834.510	135	7.367	142.033	1014.767
1995	4	9850.973	136	7.133	143.067	1034.100
1996	1	9908.347	137	7.067	144.100	1062.867
1996	2	9955.641	138	6.800	144.767	1094.333
1996	3	10091.049	139	6.633	145.967	1122.267
1996	4	10188.954	140	6.567	146.700	1136.000
1997	1	10327.019	141	6.200	147.533	1143.200
1997	2	10387.382	142	6.000	148.900	1151.067
1997	3	10506.372	143	5.633	149.767	1150.600
1997	4	10543.644	144	5.467	150.867	1148.500
1998	1	10575.100	145	5.667	152.100	1146.267
1998	2	10665.060	146	5.667	152.867	1144.300
1998	3	10737.478	147	5.567	153.700	1132.967
1998	4	10817.896	148	5.533	155.067	1121.533
1999	1	10998.322	149	5.500	156.400	1118.833
1999	2	11096.976	150	5.267	157.300	1103.400
1999	3	11212.205	151	5.333	158.667	1083.500
1999	4	11284.587	152	5.233	159.633	1077.500
2000	1	11472.137	153	5.000	160.000	1064.600
2000	2	11615.636	154	4.867	160.800	1069.233
2000	3	11715.393	155	4.667	161.667	1069.600
2000	4	11832.486	156	4.633	162.000	1076.233
2001	1	11942.032	157	4.400	162.533	1077.300
2001	2	12091.614	158	4.533	163.367	1076.967
2001	3	12287.000	159	4.433	164.133	1091.967
2001	4	12403.293	160	4.300	164.733	1097.133
2002	1	12498.694	161	4.267	165.967	1101.733
2002	2	12662.385	162	4.233	167.200	1098.267
2002	3	12877.593	163	4.067	168.433	1112.067
2002	4	12924.179	164	4.033	170.100	1112.767
2003	1	13160.842	165	3.933	171.433	1107.733
2003	2	13178.419	166	4.000	173.000	1101.133
2003	3	13260.506	167	3.900	174.233	1093.233
2003	4	13222.690	168	4.233	175.900	1102.300
2004	1	13299.984	169	4.400	177.133	1120.467
2004	2	13244.784	170	4.833	177.633	1164.867
2004	3	13280.859	171	5.500	177.500	1173.233
2004	4	13397.002	172	5.700	178.067	1191.500
2005	1	13478.152	173	5.833	179.467	1189.767
2005	2	13538.072	174	5.733	180.433	1194.100
2005	3	13559.032	175	5.867	181.500	1211.233
2005	4	13634.253	176	5.867	183.367	1235.000
2006	1	13751.543	177	6.133	183.067	1266.533
2006	2	13985.073	178	6.133	184.433	1293.633
2006	3	14145.645	179	5.833	185.133	1301.033
2006	4	14221.147	180	5.700	186.700	1318.933
2007	1	14329.523	181	5.600	188.167	1336.100
2007	2	14464.984	182	5.433	189.367	1352.267
2007	3	14609.876	183	5.433	191.400	1370.900
2007	4	14771.602	184	5.300	192.367	1370.267
2008	1	14839.782	185	5.100	193.667	1367.833
2008	2	14972.054	186	4.967	196.600	1374.433
2008	3	15066.597	187	4.967	198.433	1375.800
2008	4	15267.026	188	4.733	199.467	1381.533
2009	1	15302.705	189	4.633	201.267	1380.867
2009	2	15326.368	190	4.633	203.167	1368.567
2009	3	15456.928	191	4.433	202.333	1369.400
2009	4	15493.328	192	4.500	204.317	1368.867
2010	1	15582.085	193	4.500	206.631	1375.167
2010	2	15666.738	194	4.667	207.939	1372.900
2010	3	15761.967	195	4.800	210.490	1375.100
2010	4	15671.383	196	5.000	212.770	1384.500
2011	1	15752.308	197	5.333	215.538	1395.833
2011	2	15667.032	198	6.000	218.861	1428.133
2011	3	15328.027	199	6.867	213.849	1530.300
2011	4	15155.940	200	8.267	212.378	1579.300
2012	1	15134.117	201	9.300	213.507	1628.533
2012	2	15189.222	202	9.633	215.344	1660.000
2012	3	15356.058	203	9.933	217.030	1684.533
2012	4	15415.145	204	9.833	217.374	1698.333
2013	1	15557.277	205	9.633	217.297	1712.967
2013	2	15671.967	206	9.467	217.934	1744.200
2013	3	15750.625	207	9.500	219.699	1815.067
2013	4	15712.754	208	9.033	222.044	1875.033
2014	1	15825.096	209	9.067	224.568	1931.200
2014	2	15820.700	210	9.000	226.033	2079.033
2014	3	16004.107	211	8.633	227.047	2156.600
2014	4	16129.418	212	8.267	228.326	2215.733
2015	1	16198.807	213	8.200	228.808	2260.367
2015	2	16220.667	214	8.033	229.841	2351.000
2015	3	16239.138	215	7.800	231.369	2435.233
2015	4	16382.964	216	7.733	232.299	2476.633
2016	1	16403.180	217	7.533	232.045	2525.733
2016	2	16531.685	218	7.233	233.300	2559.767
2016	3	16663.649	219	6.933	234.163	2636.767
2016	4	16621.696	220	6.667	235.608	2727.167
2017	1	16830.111	221	6.233	236.839	2801.367
2017	2	17033.572	222	6.100	237.459	2834.133
2017	3	17113.945	223	5.700	236.920	2897.533
2017	4	17254.744	224	5.567	235.355	2984.600
2018	1	17397.029	225	5.400	236.912	3003.133
2018	2	17438.802	226	5.100	237.816	3035.233
2018	3	17456.225	227	5.000	237.888	3063.967
2018	4	17523.374	228	4.933	237.848	3131.067
2019	1	17622.486	229	4.867	239.452	3231.567
2019	2	17706.705	230	4.933	240.548	3296.700
2019	3	17784.185	231	4.733	242.177	3342.467
2019	4	17863.023	232	4.667	243.949	3411.500
2020	1	17995.150	233	4.333	244.010	3483.433
2020	2	18120.843	234	4.300	245.297	3552.767
2020	3	18223.758	235	4.100	247.301	3598.967
2020	4	18323.963	236	4.100	249.442	3641.900
2021	1	18511.576	237	3.900	250.468	3657.567
2021	2	19465.195	238	5.100	273.138	3770.667