I guess it really depends on the tax laws that are applied to your home country quite honestly.
As an example, I'll show you what happens in my country whenever you have gains (profit) on the global activity (1 year) of trading stocks:
01/01/2020 - You buy 10 Stocks of Bitcoin Incorporated each at 100 dollars. You end up spending 1.000 USD.
31/01/2020 - BTC Incorporated had a tremendous Q4 and EOY results which made it hit 200 USD per shares at the end of the month. You're shares now are evaluated at 2.000 USD
You decide to sell those shares (you fear that the price may drop slightly given the recent price increase). You recover your initial 1.000 USD investment and you also get 1.000 USD as net profit. According to the law those 1.000 USD are taxable (let's say 20 %). After paying your taxes you're left with 800 USD for your own.
However, you are a skilled trader (or at least you think you are) and you decide that you should take that profit and invest it in Defining Field Pharmaceutical at 01/02/2020, a company that's about to launch the results of the effectiveness of the COVID-19 vaccine. You get 100 stocks of that company for 10 USD each spending your 1.000 USD profit from before.
However, the trickster of COVID-19 proved to be quite sneasy and the results, published on 15/02/2020, revealed that the vaccine was only 20 % effective against the virus. The stock price went to 5 USD per stock. Your investment is now evaluated at 500 USD.
You decide that noone knows what might happen next and you sell all your position, netting you 500 USD. You had a net loss of -500 USD.
In the global fiscal year your tax payable profits would be : 1.000 USD from BTC Incorporated - 500 USD from Defining Field Pharmaceutical = 500 USD. From those you would be left with 400 USD after paying your taxes to the government.
Again, this is just a simple calculation. In a similar set of orders, but being made on the stock market, the FIFO method is a tool that could be used in order to calculate the gains that one had over the course of several interactions of the same stock (1st bough is compared with 1st sold and so on).
This is, of course, only applied to stocks/financial products and it varies according to the country. According to your "movements" you would only have to sum all the gains ((1050-1000) + (1020-1050) + (1609-(1020+480))) = £129 .
This calculation can be wrong OP and I definetly recommend you to look for real financial help form a certified accountant. The official government page from UK[1] actually has some examples on this :
Example
Victoria bought 100 token A for £1,000. A year later Victoria bought a further 50 token A for £125,000. Victoria is treated as having a single pool of 150 of token A and total allowable costs of £126,000.
A few years later Victoria sells 50 of her token A for £300,000. Victoria will be allowed to deduct a proportion of the pooled allowable costs when working out her gain:
Amount
Consideration £300,000
Less allowable costs £126,000 x (50 / 150) £42,000
Gain £258,000
Victoria will have a gain of £258,000 and she will need to pay Capital Gains Tax on this. After the sale, Victoria will be treated as having a single pool of 100 token A and total allowable costs of £84,000.
If Victoria then sold all 100 of her remaining token A then she can deduct all £84,000 of allowable costs when working out her gain.
[1]
https://www.gov.uk/government/publications/tax-on-cryptoassets/cryptoassets-for-individuals