time	PET	ET_QC
datetime
2015-01-01	1420070400000	63.0	0
2015-01-09	1420761600000	76.0	0
2015-01-17	1421452800000	44.0	0
2015-01-25	1422144000000	NaN	105
2015-02-02	1422835200000	NaN	8