difficulty does not change daily
but you can do some better math to show a different number at the next change. where you are measuring it out per day/fortnight

but at this periods difficulty and resultant of hashes. thats the math for TODAY

whom ever said nothing changes

i was using an example of TODAYs cost per btc.. thus the costs need to be broken down to per btc amount based on.. TODAYS number of todays hashrate

yes you can change the hashrate to be tomorrows hashrate. but tomorrows number would be tomorrows number.

next weeks number would be next weeks number.
but todays number is todays number


the hashrate for TODAYS number was taken into account because it used TODAYS hashrate

---

now with that said
i personally dont do daily valuations. i prefer valuations of 6-24 month averages
this is because asic farms of the most efficient variety are stuck in contracts of such lengths so they only value their rewarded coins based on such periods

they dont count in 6.25btc per block. they count in 6-24month amounts

but for simple math. becasue you perfer the difficulty period premiss

knowing there are 336 hours per period
knowing there are 2016 blocks of 6.25btc = 12600

and the hashrate is average of 315exa(per second) for this current period

lets do the math for the period and then break it down to per btc rate

hardware life cycle =2 years meaning 52 periods

so
315exa 190thash asic
= 1657894 asics  x $3629
= $6016497326 2 year life cost52
= 115701871.6538462

which of the 12600 of same period
=$9182.69 hardware cost per btc based on a fortnight period

now electric
= 1657894 asics  x 5.2
= 8621048.8kwh x 336(2 weeks of hours)
= 2896672396.8kw per fortnight x $0.04
= $115866895.872 electric per fortnight12600 btc
= $9195.79 electric per btc based on fortnightly period

which is $18378.48/btc based on fortnightly average

which is still not much different to daily average.
unlike your math showing a number at $28k


im sorry to tell you this but if the most efficient asics ON THE PLANET can only mine at $28k(your math) they would not be mining right now

the reason we have miners right now is because the efficient miners can mine for profit so your numbers are still too high to be VALUE

its not about the price they sell at
value is not even associated with the market

their selling of the coin has nothing to do with market price
value is a metric outside and away from the market price

it sits below the markets but has a cascading affect

if no one can acquire bitcoin for less than X by any means at all via net method. thats the value line

now guess whats the best method to acquire coin today..
work it out

i do laugh when people think price is value
i also laugh when people think that value does not exist or is a whole random set of numbers that become meaningless

its like they think a pint of milks value is the retail price
even though the actual value starts at the cost to milk the cow an pasteurise it

what happens after that is where middle men make profit and sell and resel until it reaches the retail market

yet if people can get milk for less then retail then the retail price is not the underlying value

the PRICE is the speculative thing.. not value
the PRICE changes and has unpredictability. but the underlying value is measurable and not volatile

heck even back in 2010 when markets were first being made. they knew about value vs price

people in the CPU solo mining era worked out their PC would have a lifespan of 5 years so they calculated how much that would be per month/week/day

then they calculated how many blocks/coins they would get per day/week/month

and also how much electric they used over the period

..
then and only then they would work out how much profit they wanted. and how much demand their was and how much they wanted to keep hold of vs sell. to come up with a preferential(emotionally driven) PRICE they would want to sell for and refuse to sell below

back then it worked out as cents per btc..

costs have increased over the years and now the bottom is many many thousands of dollars underlying cost

and again. working out of all the peoples different costs. you see a void area at the bottom where no ones costs can come below. and thats the bottomline value

but hey if codebear wants to think currency has no value and is just random.. thats on him for not thinking outside of the retail market

how many times can people shout market. but not realise they are talking about market which has nothing to do with value

value is not seen on the market so when talking about value stop saying market
you wont find a value measure on the retail spot market

PRICE is on the market and PRICE is speculative

value sits below the market and is underlying value of the world metrics of costs

yes different people have different costs but again think about costs not the retail market

then when viewing only the costs find the most cheapest efficient cost you can and you will see that number is non zero

if anyone mentions market in the same sentiment as value. they have already missed the point

This is how intrinsic value of commodities is being measured based on production costs.

Construction is a bad example.
Gold is a good one.

bitcoin production costs have a flaw and a ceiling.. that moves over time dependant on competition

the MARKET PRICE moves within that window. INBETWEEN the floor and ceiling

yes if the market stays up in the higher half of the window long enough then the competition sustainability also moves up quicker.. or if the market price does not move into the upper half then the floor ceiling window moves slowly based on the halving cycle alone

i know people get obsessed with only looking at market data and only want to point finger at the market data as the sole function of bitcoin. but there are more elements and more fundamentals outside of the market data that actually cause the price discovery


after all if every man and his dog could cpu mine bitcoin at an average of 1cent per btc cost. do you really think the markets will be at $28k speculation today.. nope every man and his dog would be selling down the market to correct the price down to cpu mining cost with only a small profit margin of speculation.

no one would even dare want to buy bitcoin for $28k if they could self mine for 1 cent
its called economics, common sense, logic

thank you for finally being part of the conversation where you now realise the cost is beneath the market price for a few lucky few.. welcome to economic fundamentals, im glad you finally arrived into the conversation with your realisation

thank you for realising the mining competition then pushes up the underlying cost, where the rise in cost leaves a non zero bottom no one goes below.. where the market then sits above the cost bottom

now run your scenario through a few competition and halving cycles as if your running it through 14 years of value rising and "price discovery".. and come to a position of 2023

where a few lucky people get to mine at $18k.. no one below..  and the rest speculate above $18k on the spot market

do you finally see it.. ?

what you need next to realise, is these lucky few most efficient miners on the planet are not paying bills per block. nor changing asics per block

they buy asics in bulk that have a 2 year lifecycle before upgrading
they also dont pay electric monthly. they instead prebuy lumps of MWH to cover a 6-24month running period. to get the best electric contract deals

and so this set 2 year cost is set. and they look at how much coin they have acquired in that long period. to come to their $18k cost per coin

now i hope you can see where the whole ROI part comes into the economics of the underlying value line