MATLAB: How to perform fft – Math Solves Everything

I have 1000 samples from an experiment with frequency Fs=67890 Hz. How can I perform fft on them? I followed the guide here https://uk.mathworks.com/help/matlab/ref/fft.html but it seems that the dominant frequency is zero which has no physical meaning.
These are my data


x =

    0.3551
    0.2308
    0.3209
    0.4527
    0.4606
    0.4511
    0.4925
    0.4769
    0.5424
    0.4698
    0.4246
    0.4502
    0.5823
    0.5451
    0.4235
    0.4062
    0.3832
    0.2749
    0.1591
    0.1889
    0.4155
    0.3840
    0.3582
    0.1852
    0.2677
    0.2454
    0.2458
    0.2100
    0.1469
    0.1186
         0
    0.4154
    0.4807
    0.4320
    0.4072
    0.3352
    0.3357
    0.2770
    0.2801
    0.3578
    0.2703
    0.3626
    0.0998
    0.3656
    0.2590
    0.4388
    0.4144
    0.2631
         0
    0.1076
         0
    0.4535
    0.4626
    0.4159
    0.3686
    0.4763
    0.2582
    0.2961
    0.3691
    0.3860
    0.3875
    0.4018
    0.4292
    0.3921
    0.3128
    0.4884
    0.3153
    0.2672
    0.3448
    0.3787
    0.4799
    0.3870
    0.3534
    0.3968
    0.3006
    0.3119
    0.3585
    0.1352
    0.4154
    0.3323
    0.3733
    0.3232
    0.4116
    0.3276
    0.4852
    0.3715
    0.3991
    0.3766
    0.4866
    0.3483
    0.2736
    0.3153
    0.4049
    0.3774
    0.3071
    0.3831
    0.3992
    0.3661
    0.3337
    0.1616
    0.3305
    0.4556
    0.5053
    0.4209
    0.2868
    0.2666
    0.3057
    0.4016
    0.2579
    0.4286
    0.1672
    0.4614
    0.3814
    0.4272
    0.3374
    0.4215
    0.4788
    0.3943
    0.4097
    0.3937
    0.4230
    0.4981
    0.4821
    0.1748
    0.4015
    0.5066
    0.4959
    0.4267
    0.4692
    0.3354
    0.2919
    0.5676
    0.4875
    0.4957
    0.4122
    0.5627
    0.4573
    0.3724
    0.4320
    0.4127
    0.3655
    0.3132
    0.1982
    0.2905
    0.3757
    0.5282
    0.4584
    0.4669
    0.4059
    0.3229
    0.4696
    0.3960
    0.5024
    0.4505
    0.4084
    0.4720
    0.4251
    0.3683
    0.3791
    0.3650
    0.2426
    0.3169
    0.4405
    0.4129
    0.4839
    0.3578
    0.3550
    0.4090
    0.4063
    0.4497
    0.5195
    0.4645
    0.4514
    0.4375
    0.3405
    0.5263
    0.4195
    0.3746
    0.2887
    0.4121
    0.3987
    0.4428
    0.4065
    0.3340
    0.3511
    0.3328
    0.3698
    0.4988
    0.3478
    0.2817
    0.2795
    0.4926
    0.3976
    0.3728
    0.4816
    0.4690
    0.4328
    0.6150
    0.1455
    0.3981
    0.3184
    0.4321
    0.3678
    0.3407
    0.2930
    0.3325
    0.5747
    0.5205
    0.4418
    0.4604
    0.3597
    0.3404
    0.3153
    0.5779
    0.3666
    0.3215
    0.2842
    0.2314
    0.2940
    0.3745
    0.3215
    0.2711
    0.3004
    0.3946
    0.3942
    0.3256
    0.2587
    0.3177
    0.2474
    0.2057
    0.4025
    0.4435
    0.4262
    0.3123
    0.3033
    0.3595
    0.3224
    0.5162
    0.5210
    0.5185
    0.5082
    0.5174
    0.4634
    0.4224
    0.5525
    0.4637
    0.5132
    0.5806
    0.3519
    0.5952
    0.5103
    0.4021
    0.3890
    0.3671
    0.5863
    0.3946
    0.3198
    0.1014
    0.4934
    0.4089
    0.5890
    0.4601
    0.5628
    0.5392
    0.4553
    0.4755
    0.5468
    0.4478
    0.4900
    0.3323
    0.2200
    0.4340
    0.4119
    0.4075
    0.3577
    0.5101
    0.3585
    0.3939
    0.4366
    0.3738
    0.3934
    0.4416
    0.4464
    0.3510
    0.3791
    0.4289
    0.3966
    0.3113
    0.2998
    0.4251
    0.4033
    0.3393
    0.3843
    0.4246
    0.4224
    0.4072
    0.2900
    0.4400
    0.5314
    0.4580
    0.4382
    0.4118
    0.4298
    0.5275
    0.4492
    0.4100
    0.4098
    0.4530
    0.4531
    0.4177
    0.5175
    0.2001
    0.5330
    0.4534
    0.4613
    0.0637
    0.4619
    0.5318
    0.4129
    0.3292
    0.3293
    0.4428
    0.3560
    0.4558
    0.3736
    0.2481
    0.3881
    0.3586
    0.3284
    0.0465
    0.3070
    0.4227
    0.3891
    0.3911
    0.5650
    0.3529
    0.3481
    0.3482
    0.3682
    0.5319
    0.5387
    0.1824
    0.3062
    0.4315
    0.4625
    0.3685
    0.5253
    0.4801
    0.5584
    0.4634
    0.5326
    0.4494
    0.4534
    0.4064
    0.3226
    0.1444
    0.4603
    0.4277
         0
    0.3656
    0.4511
    0.5926
    0.4544
    0.4301
    0.3542
    0.3607
    0.3684
    0.4694
    0.5180
    0.3940
    0.4657
    0.3901
    0.4060
    0.3740
    0.3351
    0.3571
    0.3845
    0.3225
    0.4296
    0.3675
    0.4469
    0.3926
    0.3571
    0.3877
    0.2835
    0.4564
    0.4695
    0.3038
    0.4322
    0.3454
    0.4157
    0.4131
    0.3656
    0.3244
    0.3835
    0.3835
    0.3669
    0.3769
    0.3392
    0.4072
    0.4156
    0.4026
    0.4092
    0.3624
    0.4615
    0.3921
    0.4848
    0.4077
    0.2904
    0.3404
    0.3485
    0.4472
    0.4097
    0.3488
    0.3555
    0.2958
    0.1905
    0.2594
    0.5082
    0.3526
    0.5096
    0.2486
    0.3777
    0.3662
    0.4036
    0.4170
    0.4132
    0.4760
    0.4813
    0.2767
    0.4714
    0.3762
    0.3883
    0.2067
    0.1974
    0.3166
    0.3852
    0.2576
    0.3949
    0.2443
    0.3779
    0.4300
    0.3881
    0.3786
    0.3516
    0.4147
    0.3850
    0.4277
    0.4620
    0.4737

            
            

    
        
	
    
        Best Answer
    

    
								
								[moved from comments]
To remove the 0Hz-component from the analysis, use y=fft(x-mean(x));
						    
								
    
        
    

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