This question shall be answered by the analysis of some data from the application coin-doubler.

How does coin-doubler work

This application generates profits in the cryptoscene by using the most advanced technology and everybody can benefit from it by "donations". Donations to coin-doubler are rewarded with twice the amount in the same token over an unspecified period of time, also as a gift.

Evaluation of a randomly selected donation

The user marett has donated 3,400.000 STEEM to coin-doubler with this transaction 15f9c18e25b83d9a4973f9a3079be30a7b4ce588 on 11/16/2020 UTC.

List of the gifts

The table below lists the corresponding gifts which the user marett has received from coin-doubler.

#	Date	Gift	TX
1	11/17/2020	134.339 STEEM	d03159f983e7af9f320a5f69c64b4edacf4e87d2
2	11/18/2020	106.911 STEEM	a6aebd3cc9785838c47d26e5dd04b0651b6dcff4
3	11/19/2020	107.360 STEEM	e7d682ad1d39ef48dfa0abd40598f450b480eebc
4	11/20/2020	122.817 STEEM	dbf3389a5372d09ae41b66af097df772ed65e85e
5	11/21/2020	109.660 STEEM	a53215637974ce235dfc0f4bdc81b2490cc5b298
6	11/22/2020	117.264 STEEM	ce76fa961e82764b8b92c45f42afbce12ce4e88d
7	11/23/2020	105.716 STEEM	d5b9c9ae4c533cc70789c1fb0ca5c3a8b9e121f8
8	11/24/2020	110.771 STEEM	0dd0123e76d223274589867e932736847f227e49
9	11/25/2020	103.579 STEEM	345cd63a1e848fa8d9cbffe781adfd7cf5bed529
10	11/26/2020	108.658 STEEM	07ed91548966d8e71c855003d65fe70d21c7e4a1
11	11/27/2020	130.830 STEEM	f3257d036e30d048a97447a66c8f0f34e2bf5357
12	11/28/2020	128.735 STEEM	59746b52f996a5f434edaccefa53314e74150dab
13	11/29/2020	117.863 STEEM	8116415627b959d23bb83c17586df1674e9708e8
14	11/30/2020	111.251 STEEM	bcdd8d54922715cf7113d10e4860b22eb03d3e85
15	12/01/2020	127.592 STEEM	3b4b8126edcc2fdb474f5d4e2c5d39de15c8d7d7
16	12/02/2020	122.153 STEEM	c26c109f0d5e5ede0582fee5faf89eaeba7064bd
17	12/03/2020	112.257 STEEM	fdb99c6b997a8d459f0ca43447aefd7ec522320e
18	12/04/2020	110.661 STEEM	de8b8f820d33efe542335171b35d740ceabd4a52
19	12/05/2020	126.082 STEEM	6533765c75c3725740c7256d1353522480f9c5f5
20	12/06/2020	134.575 STEEM	5e19c0abbc87ac0763cec4a9d9d68ef5faaaa518
21	12/07/2020	114.034 STEEM	285be006b38983c04979c24a790a8cdabc811ac9
22	12/08/2020	109.241 STEEM	a4f97b0f291ede2fb56cb729932efce22c1d24ed
23	12/09/2020	105.929 STEEM	e6c57cfb931913807a927b70ea9e4d60d2257c7d
24	12/10/2020	132.530 STEEM	8048df27e9835d99165677abebb285fe6d603a89
25	12/11/2020	118.063 STEEM	758aa97d51acda894267cd03e0ada66bba5baf7a
26	12/12/2020	123.236 STEEM	17e7b00160f147714af8f584fb7a989c0716a486
27	12/13/2020	112.668 STEEM	ca18654d0bc32e9508fb49e89e17c9233eef276d
28	12/14/2020	103.072 STEEM	60204a85fbff5f74bfe0fdc154ace6e42001e10d
29	12/15/2020	118.590 STEEM	954bd7b0bbd0c46fb7712319985db88fee41d919
30	12/16/2020	111.457 STEEM	b2a1885dc5963d7c6e2535d28ce3b98cc0291cfc
31	12/17/2020	129.284 STEEM	bff60053e8598f38302c14040d2181eaea9705c7
32	12/18/2020	132.129 STEEM	052aa221afab5b201898578c430ab3f66b7b9439
33	12/19/2020	117.070 STEEM	6b43e57caae57f8a1e9b8491c85961bbf0e94940
34	12/20/2020	116.954 STEEM	5e9d465d9f24d94e1079cf02ca772dcaf6bbf587
35	12/21/2020	117.568 STEEM	ef0b3f343da87ac78acb65cbf0146811a755bea4
36	12/22/2020	105.188 STEEM	222aefb8b6f160cdf944bd50fab043df54bde7b3
37	12/23/2020	103.141 STEEM	57d6b73cf792a6a6e3625e793e1b7394e6319e22
38	12/24/2020	110.935 STEEM	2ff88180fd4266e1f295301dced4b04802008e19
39	12/25/2020	129.590 STEEM	fcd07d4c90ff2a1f7884835fa4e6256fb02aa8ad
40	12/26/2020	117.926 STEEM	442847e4b4176e2ed84a253dbac963e2f426441a
41	12/27/2020	120.962 STEEM	864690f7b055000899cbdd8be26ea3f88c644079
42	12/28/2020	123.952 STEEM	1657c723ca1d50109468501ddf76ecd8893a5cee
43	12/29/2020	115.910 STEEM	571b3c414268d9ed609e2fcd79beae733431acc7
44	12/30/2020	125.273 STEEM	988337aa37704b8328787c5fa281ae9f538a6fb9
45	12/31/2020	120.480 STEEM	926137ed39128248cc4775550735765ec8bf623f
46	01/01/2021	118.943 STEEM	1a0064c912e2abce524a5c193a895a8b4fc5838a
47	01/02/2021	114.982 STEEM	56d6d24c014d9489dd25b9af04314562e5718851
48	01/03/2021	129.641 STEEM	337184d4827fb500a712bbdb10acf56f98037c2f
49	01/04/2021	126.673 STEEM	7d7aff417074ee4d56dc538dc4fa3ba9a49e9074
50	01/05/2021	124.423 STEEM	914b4a767ce7b3ccfe4424ec5a3d7afb2a59cf2e
51	01/06/2021	117.091 STEEM	ffafb555fba7c53fbf14d125ac890a8af2e88bc9
52	01/07/2021	119.327 STEEM	8dd7cba7a0f4f6851bf8165ad22ed265f52d179f
53	01/08/2021	106.162 STEEM	829530b47333274d6fe604f73b51e7dc8b1d7d78
54	01/09/2021	130.058 STEEM	df4267db6db7f8b1168a0eaa846c40a2f990031f
55	01/10/2021	126.234 STEEM	9d932a80431681fb48c1ed71f27ec4b5622cdd83
56	01/11/2021	102.890 STEEM	698a331405806413b473c7c2ff46341bdc4d3be8
57	01/12/2021	103.789 STEEM	8eb7da6e23784793b82031d9e516257377ec488e
58	01/13/2021	95.531 STEEM	f6c7b6eb86389884eea2dd9c5c768accbcbad083

Total: 6,800.000 STEEM

Summary

The user marett has been rewarded with twice the amount of the "donation" within 58 days.

Technical Analysis for STEEM

As the application coin-doubler has the potential to attract numerous investors, STEEM's price is expected to rise.

Technical Analysis for STEEM crypto currency

Boost My Wealth Challenge

If you want to participate from the Steem ecosystem's success, you can do so right now by following a few simple steps.

All author reward from this account will be paid out for an indefinite period of time to 8 participants per comment as Beneficiary Reward.

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Type in abandi and click "SET PROXY". Currently this account is voting for the following witnesses as they are the ones who can ensure the safe operation of the Steem blockchain: beargame, cryptoking777, dev.supporters, dlike, enjoylondon, exnihilo.witness, future.witness, hinomaru-jp, hoasen, inwi, juddsmith079, justyy, leverfile, maiyude, matreshka, menacamel, parse, protoss20, rlawlstn123, rnt1, roadofrich, roundblocknew, scissor.sisters, smt-wherein, steem-agora, steem-dragon, steem-supporter, steem.history, steemchiller and upeross.
Invest for your bright future by buying some STEEM regularly and only selling some of the profit if necessary. (Think about the power of compound interest.)
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Beneficiaries of this post

Following users will receive 12.5% from the Author Reward each: abduloniz, cumaeker, iphy2013, letsplaywhatelse, makm, maxipack, razeiv and sumeyraece.

Information for beneficiaries, your Upvote on this post will earn you an additional 12.5% Beneficiary Reward to your Curation Reward.

Users on the radar for upcoming Beneficiary Rewards

Following users have also appeared on the radar: andrew-luck, blckchainboogiee, blockchainnerd, cloud1985, dara-aceh, fernando-alonso, havvaakdemir, jameswsparker, lalukumar, latest-marble, lebron-james, leonardo-dcaprio, mga104, mushthafakamal, pxtrx, rcarupe, royalmonk, salman-khan, shfaisalsh and yuns.dancer.

The decision has been difficult as always, but maybe it will work out in the next rounds. You get mentioned so that you at least get the attention of the followers. You have contributed to the Steem ecosystem's success as well, thank you.