Yes you can do in MT4 and MT5. The formula is: N = 0.5 * [(1 + 8 * P/delta) ^ 0.5 + 1]
where N is the number of lots, P is the total closed trade profit, and delta is the parameter discussed above. The carat symbol (^) represents exponentiation; that is, the quantity in parentheses is raised to the power of 0.5 (square root).
A few points are worth noting. The profit, P, is the accumulated profit over all trades leading up to the one for which you want to calculate the number of lots. Consequently, the number of lots for the first trade is always one because you always start with zero profits (P = 0). Also, as you accrue more profits, the number of lots increases more slowly. The $ 10,000 profit made early in the sequence of trades will increase the number of lotts more than a $ 10,000 profit made after many other profitable trades.
Ryan Jones, who is the creator of Fixed Ratio system, says that the difference is in the general problem with the fixed fractional method is that the risk premium associated with the batch size is very low when the Bill is small and very loud when the account is great. Already the Fixed Ratio method allows the account to grow aggressively in the beginning, assuming more risk, and gradually reduces the risk that the account size grows. The main principle behind fixed aspect ratio is the ratio between the number of lots sold and the amount of earnings required to increase the number of lots traded remains fixed.
According to the Fixed Ratio money management method proposed by Ryan Jones, before you can add a lot to an existing number of lots, each of the existing lots shall "win" a certain number of points (which Jones called the "delta"). For example, we have a deposit of 300 dollars and trade with 1 mini lot; the delta of, say, the same 300 dollars would mean that we will increase to 2 mini lots only when we gain (with the 1 mini lot we have) 300 dollars.
Similarly, the lots will be increased to 3 only after 2 mini lots will gain the delta of 300 dollars (each). That is, the increase from 2 to 3 mini lots will be possible when we add to the existing 600 dollars another 2 С ... $ 300 = $ 600, i.e. when having $ 1200; from 3 to 4 mini lots with the deposit of $ 1200 + ($ 300 С ... 3) = $ 1200 + $ 900 = $ 2100, etc. Thus, "the number of contracts is proportional to the amount required to buy new number of contracts", from where the method derives its name. The decrease in the number of lots follows the same scheme in reverse.
Source: http://www.mql5.com/en/articles/392
In short: This Fixed Ratio relationship can be expressed as: The New Account Level to Increase Trade by One Lot Size = Starting Account Value + (Delta x Number of Current Lots)
More information and comparative tables you can also be found in the book also Automatic Alpha, David J. Lyder.