How to calculate span loss submarine cable?

Dear friend！
Submarine optical cables usually use Coming(R) Vascade(R) EX2000 optical fibers with large effective area and ultra-low loss. The average attenuation is 0.158 dB/km. The attenuation change during the whole production process is less than or equal to ±0.008 dB/km.
The point loss of the movable joint shall not be greater than 0.5 dB. If the splicing loss is less than 0.03 dB, test the splicing loss of 0.08 dB.
0.158 dB/km x Total km + Active linker 0.5 dB x n1 + Splicing loss 0.08 x n2 = Total loss
n1 is the number of active linkers, and n2 is the number of splicing points.

Please note that the above is a reference only. The standards may vary from country to country. In addition, the calculation method varies in different scenarios.

Thank you！