detail and approximation coefficients of discrete wavelet transform

Matlab code to extract coefficients (detail and approximation), and corresponding energy. Formula for energy is shwn in in attached image.

While trying this commands, why cd1 (11 samples), cd2(9 samples) cd3 (8 samples) and cd4 (7 samples) samples are different even the original signal contain 16 samples.

[C,L] = wavedec(inrush1_final(1:16,1),4,'db4');

approx = appcoef(C,L,'db4');

[cd1,cd2,cd3,cd4] = detcoef(C,L,[1 2 3 4]);

[Ea,Ed] = wenergy(C,L)