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I'm trying to replicate the following delta hedging table from hull(10th ed, table 19.2): Older ed How to understand this example from Hull's book?

                                   Cumulative Interest
W   S   Delta Shares  C   Cost*1000 Cost+r     cost*1000  
0 49.00 0.522 52000  2.40 2,557.8   2,557.8     2.5
1 48.12 0.458 -6,400 1.88 -308.0    2,252.3     2.2
2 47.37 0.400 -5,800 1.48 -274.7    1,979.8     1.9
3 50.25 0.596 19.600 2.83 984.9     2,966.6     2.9
4 51.75 0.693 9.700  3.71 502.0     3,471.5     3.3
5 53.12 0.774 8.100  4.62 430.3     3,905.1     3.8

Parameters are: $S0 =49; K=50; r=0.05 (annual); 􏰉\sigma= 20; T=0:3846 (20weeks); 􏰐\mu=0.13$ So we sell 100.000 call options:

At t = 0; Cash = C0*100.000 = 240.000, Balance = 52500 stocks * S0 (= 49) = 2,557.800USD that we need to borrow at the rate of 0.05.

Here it says in the text: "An interest cost of approximately $2,500 is therefore incurred in the first week". However can someone explain how the cumulative cost are calculated? No matter what I do I seem to get a total costs of 5,260.801 what means the hedge costs are 260.801 what means a loss on this position of 20.801. In the example at maturity we have total cost of 5,263.300 which means cost of the hedge are 263,300 and thus a loss of 13,300.

Can someone explain the iterative procedure how to calculate the values of the table. I've tried different ways (programmed in python and Matlab and other examples on the internet as well) however I am not able to replicate the results of this table. If you would able to provide the formulas + numerical solution for t = 1, t = 2 and t = maturity so I can move on.

How to understand this example from Hull's book?

https://quant.stackexchange.com/a/35733

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    $\begingroup$ The interest cost is computed in one row and then added to 'Cumulative cost+r' in the next row. For example 2557.8+2.5-308.0 -> 2252.3 in row 1. Then 2252.3+2.2-274.7 -> 1979.8 in row 2. And so forth $\endgroup$ – noob2 Sep 30 '20 at 19:50
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    $\begingroup$ And how it the interest cost computed? For example 3905.1*(exp(0.05/52)-1) -> 3.7567, which is rounded up to 3.8. $\endgroup$ – noob2 Sep 30 '20 at 19:58
  • $\begingroup$ Hey noob2, can you give a formula for how they compute the total hedge cost and PnL at maturity? All your other solutions worked! $\endgroup$ – wecandothis Oct 1 '20 at 12:23
  • $\begingroup$ Btw; if I follow the code given in nms.kcl.ac.uk/john.armstrong/courses/fm06/book/… I get other Profit and Loss values; really annoying $\endgroup$ – wecandothis Oct 1 '20 at 12:44
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    $\begingroup$ I have somewhat lost track of what the question is at this point. If you can ask a fresh Q it might be good. $\endgroup$ – noob2 Oct 1 '20 at 13:25

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