Rapid Rescue (Alternate Art)

Challenger Series: My Hero Academia - Dark Hero Arc · #MHA08 9/20

Rapid Rescue (Alternate Art) — Challenger Series: My Hero Academia - Dark Hero Arc

Rapid Rescue (Alternate Art)

TCGPlayer · US market · FoilUS$3.13USD market referenceUpdated 24 Oct 2026
SetChallenger Series: My Hero Academia - Dark Hero Arc
NumberMHA08 9/20
RarityC-ALT
Set CodeDHA
Print Type

Rapid Rescue (Alternate Art)

TCGPlayer · US market · FoilUS$3.13USD market referenceUpdated 24 Oct 2026
▼75.92%historical change

Ungraded card references. Condition and selling costs affect what you receive; graded slab values are not covered.

Rapid Rescue (Alternate Art) #MHA08 9/20 from Challenger Series: My Hero Academia - Dark Hero Arc (Foil): TCGPlayer US-market reference US$3.13, updated 24 Oct 2026. Source currency: USD.

What does this price mean?

TCGPlayer is a US-market reference in USD. Cardmarket uses a Broad foil guide · EUR source, converted from EUR to USD; it is not UK-only pricing. Prices refer to the displayed printing. Your card's condition, language, grading and selling costs can affect what you receive.

US market price history · 11 Oct 2024 – 24 Oct 2026
719 recorded price points. Change compares the first and last points shown.

View recorded prices as a table
US market-price observations in USD · Foil
DateMarket price
11 Oct 2024$13.00
12 Oct 2024$13.00
13 Oct 2024$13.00
14 Oct 2024$13.00
15 Oct 2024$13.00
16 Oct 2024$11.50
17 Oct 2024$10.50
18 Oct 2024$10.50
19 Oct 2024$10.50
20 Oct 2024$10.50
21 Oct 2024$8.00
22 Oct 2024$7.00
23 Oct 2024$7.00
24 Oct 2024$5.00
25 Oct 2024$5.00
26 Oct 2024$5.00
27 Oct 2024$5.00
28 Oct 2024$5.00
29 Oct 2024$5.00
30 Oct 2024$5.00
31 Oct 2024$5.00
1 Nov 2024$5.31
2 Nov 2024$5.31
3 Nov 2024$5.31
4 Nov 2024$5.31
5 Nov 2024$5.31
6 Nov 2024$5.31
7 Nov 2024$5.31
8 Nov 2024$5.47
9 Nov 2024$5.47
10 Nov 2024$5.47
11 Nov 2024$5.47
12 Nov 2024$5.47
13 Nov 2024$5.47
14 Nov 2024$5.47
15 Nov 2024$5.47
16 Nov 2024$5.47
17 Nov 2024$5.47
18 Nov 2024$5.47
19 Nov 2024$5.47
20 Nov 2024$5.47
21 Nov 2024$5.47
22 Nov 2024$5.47
23 Nov 2024$5.47
24 Nov 2024$5.47
25 Nov 2024$5.47
26 Nov 2024$5.47
27 Nov 2024$5.47
28 Nov 2024$5.47
29 Nov 2024$5.47
30 Nov 2024$5.47
1 Dec 2024$5.29
2 Dec 2024$5.29
3 Dec 2024$5.29
4 Dec 2024$5.29
5 Dec 2024$5.29
6 Dec 2024$5.29
7 Dec 2024$5.29
8 Dec 2024$5.29
9 Dec 2024$5.29
10 Dec 2024$5.29
11 Dec 2024$5.29
12 Dec 2024$5.29
13 Dec 2024$5.29
14 Dec 2024$5.29
15 Dec 2024$5.29
16 Dec 2024$5.29
17 Dec 2024$5.29
18 Dec 2024$5.29
19 Dec 2024$5.29
20 Dec 2024$5.29
21 Dec 2024$5.29
22 Dec 2024$5.29
23 Dec 2024$5.29
24 Dec 2024$5.29
25 Dec 2024$5.29
26 Dec 2024$5.29
27 Dec 2024$5.29
28 Dec 2024$5.29
29 Dec 2024$5.29
30 Dec 2024$5.29
31 Dec 2024$5.29
1 Jan 2025$5.29
2 Jan 2025$5.29
3 Jan 2025$5.29
4 Jan 2025$5.29
5 Jan 2025$5.29
6 Jan 2025$5.29
7 Jan 2025$5.29
8 Jan 2025$5.29
9 Jan 2025$5.29
10 Jan 2025$4.70
11 Jan 2025$4.70
12 Jan 2025$4.70
13 Jan 2025$4.70
14 Jan 2025$4.70
15 Jan 2025$4.70
16 Jan 2025$4.70
17 Jan 2025$4.70
18 Jan 2025$4.70
19 Jan 2025$4.70
20 Jan 2025$4.70
21 Jan 2025$4.70
22 Jan 2025$4.70
23 Jan 2025$4.70
24 Jan 2025$4.70
25 Jan 2025$4.70
26 Jan 2025$4.70
27 Jan 2025$4.70
28 Jan 2025$4.70
29 Jan 2025$4.70
30 Jan 2025$4.70
31 Jan 2025$4.70
1 Feb 2025$4.70
2 Feb 2025$4.70
3 Feb 2025$4.70
4 Feb 2025$4.70
5 Feb 2025$4.70
6 Feb 2025$4.70
7 Feb 2025$4.70
8 Feb 2025$4.70
9 Feb 2025$4.70
10 Feb 2025$4.70
11 Feb 2025$4.70
12 Feb 2025$4.70
13 Feb 2025$4.70
14 Feb 2025$4.70
15 Feb 2025$4.70
16 Feb 2025$4.70
17 Feb 2025$4.70
18 Feb 2025$4.70
19 Feb 2025$4.70
20 Feb 2025$4.70
21 Feb 2025$4.70
22 Feb 2025$4.70
23 Feb 2025$4.70
24 Feb 2025$4.70
25 Feb 2025$4.70
26 Feb 2025$4.70
27 Feb 2025$4.70
28 Feb 2025$4.74
1 Mar 2025$4.74
2 Mar 2025$4.74
3 Mar 2025$4.74
4 Mar 2025$4.74
5 Mar 2025$4.74
6 Mar 2025$4.74
7 Mar 2025$4.74
8 Mar 2025$4.74
9 Mar 2025$4.74
10 Mar 2025$4.74
11 Mar 2025$4.74
12 Mar 2025$4.74
13 Mar 2025$4.74
14 Mar 2025$4.74
15 Mar 2025$4.74
16 Mar 2025$4.74
17 Mar 2025$4.74
18 Mar 2025$4.74
19 Mar 2025$5.05
20 Mar 2025$5.05
21 Mar 2025$5.05
22 Mar 2025$5.05
23 Mar 2025$5.05
24 Mar 2025$5.05
25 Mar 2025$5.05
26 Mar 2025$5.05
27 Mar 2025$5.05
28 Mar 2025$5.05
29 Mar 2025$5.05
30 Mar 2025$5.05
31 Mar 2025$5.05
1 Apr 2025$5.05
2 Apr 2025$5.05
3 Apr 2025$5.05
4 Apr 2025$5.05
5 Apr 2025$5.05
6 Apr 2025$5.05
7 Apr 2025$5.05
8 Apr 2025$5.05
9 Apr 2025$5.05
10 Apr 2025$5.05
11 Apr 2025$5.05
12 Apr 2025$5.05
13 Apr 2025$5.05
14 Apr 2025$5.05
15 Apr 2025$5.05
16 Apr 2025$5.05
17 Apr 2025$5.05
18 Apr 2025$5.05
19 Apr 2025$5.05
20 Apr 2025$5.05
21 Apr 2025$5.05
22 Apr 2025$5.05
23 Apr 2025$5.07
24 Apr 2025$5.07
25 Apr 2025$5.07
26 Apr 2025$5.07
27 Apr 2025$5.07
28 Apr 2025$5.07
29 Apr 2025$5.07
30 Apr 2025$5.07
1 May 2025$4.89
2 May 2025$4.89
3 May 2025$4.89
4 May 2025$4.89
5 May 2025$4.89
6 May 2025$4.89
7 May 2025$4.89
8 May 2025$4.89
9 May 2025$4.89
10 May 2025$4.89
11 May 2025$4.89
12 May 2025$4.89
13 May 2025$4.89
14 May 2025$4.89
15 May 2025$4.89
16 May 2025$4.89
17 May 2025$4.89
18 May 2025$4.89
19 May 2025$4.89
20 May 2025$4.89
21 May 2025$4.89
22 May 2025$4.89
23 May 2025$4.89
24 May 2025$4.89
25 May 2025$4.89
26 May 2025$4.89
27 May 2025$4.89
28 May 2025$4.89
29 May 2025$4.89
30 May 2025$4.89
31 May 2025$4.88
1 Jun 2025$4.88
2 Jun 2025$4.88
3 Jun 2025$4.88
4 Jun 2025$4.88
5 Jun 2025$4.88
6 Jun 2025$4.88
7 Jun 2025$4.88
8 Jun 2025$4.88
9 Jun 2025$4.88
10 Jun 2025$4.88
11 Jun 2025$4.88
12 Jun 2025$4.88
13 Jun 2025$4.88
14 Jun 2025$4.88
15 Jun 2025$4.88
16 Jun 2025$4.88
17 Jun 2025$4.88
18 Jun 2025$4.88
19 Jun 2025$4.88
20 Jun 2025$4.88
21 Jun 2025$4.88
22 Jun 2025$4.88
23 Jun 2025$4.88
24 Jun 2025$4.88
25 Jun 2025$4.88
26 Jun 2025$4.88
27 Jun 2025$4.88
28 Jun 2025$4.88
29 Jun 2025$4.88
30 Jun 2025$4.88
1 Jul 2025$4.88
2 Jul 2025$4.88
3 Jul 2025$4.88
4 Jul 2025$4.88
5 Jul 2025$4.88
6 Jul 2025$4.88
7 Jul 2025$4.88
8 Jul 2025$4.88
9 Jul 2025$4.88
10 Jul 2025$5.94
11 Jul 2025$5.94
12 Jul 2025$5.94
13 Jul 2025$5.94
14 Jul 2025$5.94
15 Jul 2025$5.94
16 Jul 2025$5.94
17 Jul 2025$5.94
18 Jul 2025$5.94
19 Jul 2025$5.94
20 Jul 2025$5.94
21 Jul 2025$5.94
22 Jul 2025$5.94
23 Jul 2025$5.94
24 Jul 2025$5.94
25 Jul 2025$5.94
26 Jul 2025$5.94
27 Jul 2025$5.94
28 Jul 2025$5.94
29 Jul 2025$5.94
30 Jul 2025$5.94
31 Jul 2025$5.94
1 Aug 2025$5.94
2 Aug 2025$5.94
3 Aug 2025$5.94
4 Aug 2025$5.94
5 Aug 2025$5.94
6 Aug 2025$5.94
7 Aug 2025$5.94
8 Aug 2025$5.94
9 Aug 2025$5.94
10 Aug 2025$5.94
11 Aug 2025$5.94
12 Aug 2025$5.94
13 Aug 2025$5.94
14 Aug 2025$5.94
15 Aug 2025$5.94
16 Aug 2025$5.94
17 Aug 2025$5.94
18 Aug 2025$5.94
19 Aug 2025$5.94
20 Aug 2025$5.94
21 Aug 2025$5.94
22 Aug 2025$5.94
23 Aug 2025$5.94
24 Aug 2025$5.94
25 Aug 2025$5.94
26 Aug 2025$5.94
27 Aug 2025$6.93
28 Aug 2025$5.19
29 Aug 2025$5.19
30 Aug 2025$5.19
31 Aug 2025$5.19
1 Sept 2025$5.19
2 Sept 2025$5.19
3 Sept 2025$5.19
4 Sept 2025$5.19
5 Sept 2025$5.06
6 Sept 2025$5.06
7 Sept 2025$5.06
8 Sept 2025$5.06
9 Sept 2025$5.06
10 Sept 2025$5.06
11 Sept 2025$5.06
12 Sept 2025$5.06
13 Sept 2025$5.06
14 Sept 2025$5.06
15 Sept 2025$4.13
16 Sept 2025$4.13
17 Sept 2025$4.13
18 Sept 2025$4.13
19 Sept 2025$4.13
20 Sept 2025$4.13
21 Sept 2025$4.13
22 Sept 2025$4.13
23 Sept 2025$4.13
24 Sept 2025$4.13
25 Sept 2025$4.13
26 Sept 2025$4.13
27 Sept 2025$4.13
28 Sept 2025$4.13
29 Sept 2025$4.13
30 Sept 2025$4.13
1 Oct 2025$4.13
2 Oct 2025$4.13
3 Oct 2025$4.13
4 Oct 2025$4.13
5 Oct 2025$4.13
6 Oct 2025$4.13
7 Oct 2025$4.13
8 Oct 2025$4.13
9 Oct 2025$4.13
10 Oct 2025$4.13
11 Oct 2025$4.13
12 Oct 2025$4.13
13 Oct 2025$4.13
14 Oct 2025$4.13
15 Oct 2025$4.13
16 Oct 2025$4.13
17 Oct 2025$4.13
18 Oct 2025$4.13
19 Oct 2025$4.13
20 Oct 2025$4.13
21 Oct 2025$4.13
22 Oct 2025$4.13
23 Oct 2025$4.13
24 Oct 2025$4.13
25 Oct 2025$4.13
26 Oct 2025$4.13
27 Oct 2025$4.13
28 Oct 2025$4.13
29 Oct 2025$4.13
30 Oct 2025$4.13
31 Oct 2025$4.13
1 Nov 2025$4.13
2 Nov 2025$4.13
3 Nov 2025$4.13
4 Nov 2025$4.13
5 Nov 2025$4.13
6 Nov 2025$4.13
7 Nov 2025$4.13
8 Nov 2025$4.13
9 Nov 2025$4.13
10 Nov 2025$4.13
11 Nov 2025$4.13
12 Nov 2025$4.13
13 Nov 2025$4.13
14 Nov 2025$4.13
15 Nov 2025$4.13
16 Nov 2025$4.13
17 Nov 2025$4.13
18 Nov 2025$4.13
19 Nov 2025$4.13
20 Nov 2025$4.13
21 Nov 2025$4.13
22 Nov 2025$4.13
23 Nov 2025$4.13
24 Nov 2025$4.13
25 Nov 2025$4.13
26 Nov 2025$4.13
27 Nov 2025$4.13
28 Nov 2025$4.13
29 Nov 2025$4.13
30 Nov 2025$4.13
1 Dec 2025$4.13
2 Dec 2025$4.13
3 Dec 2025$4.13
4 Dec 2025$4.13
5 Dec 2025$3.84
6 Dec 2025$3.84
7 Dec 2025$3.84
8 Dec 2025$3.84
9 Dec 2025$3.84
10 Dec 2025$3.84
11 Dec 2025$3.84
12 Dec 2025$3.84
13 Dec 2025$3.84
14 Dec 2025$3.84
15 Dec 2025$3.84
16 Dec 2025$3.84
17 Dec 2025$3.84
18 Dec 2025$3.84
19 Dec 2025$3.84
20 Dec 2025$3.84
21 Dec 2025$3.84
22 Dec 2025$3.84
23 Dec 2025$3.84
24 Dec 2025$3.84
25 Dec 2025$3.84
26 Dec 2025$3.84
27 Dec 2025$3.84
28 Dec 2025$3.84
29 Dec 2025$3.84
30 Dec 2025$3.84
31 Dec 2025$3.84
1 Jan 2026$3.84
2 Jan 2026$3.84
3 Jan 2026$3.84
4 Jan 2026$3.84
5 Jan 2026$3.84
6 Jan 2026$3.84
7 Jan 2026$3.84
8 Jan 2026$3.84
9 Jan 2026$3.84
10 Jan 2026$3.84
11 Jan 2026$3.84
12 Jan 2026$3.84
13 Jan 2026$3.84
14 Jan 2026$3.84
15 Jan 2026$3.84
16 Jan 2026$3.84
17 Jan 2026$3.84
18 Jan 2026$3.84
19 Jan 2026$3.84
20 Jan 2026$3.84
21 Jan 2026$3.84
22 Jan 2026$3.84
23 Jan 2026$3.84
24 Jan 2026$3.84
25 Jan 2026$3.84
26 Jan 2026$3.84
27 Jan 2026$3.84
28 Jan 2026$3.84
29 Jan 2026$3.84
30 Jan 2026$3.84
31 Jan 2026$3.84
1 Feb 2026$3.84
2 Feb 2026$3.84
3 Feb 2026$3.84
4 Feb 2026$3.84
5 Feb 2026$3.84
6 Feb 2026$3.84
7 Feb 2026$3.84
8 Feb 2026$3.84
9 Feb 2026$3.84
10 Feb 2026$3.84
11 Feb 2026$3.84
12 Feb 2026$3.84
13 Feb 2026$3.84
14 Feb 2026$3.84
15 Feb 2026$3.84
16 Feb 2026$3.84
17 Feb 2026$3.84
18 Feb 2026$3.84
19 Feb 2026$3.84
20 Feb 2026$3.84
21 Feb 2026$3.84
22 Feb 2026$3.84
23 Feb 2026$3.84
24 Feb 2026$4.03
25 Feb 2026$4.03
26 Feb 2026$4.03
27 Feb 2026$4.03
28 Feb 2026$4.03
1 Mar 2026$4.03
2 Mar 2026$4.03
3 Mar 2026$4.03
4 Mar 2026$4.03
5 Mar 2026$3.26
6 Mar 2026$3.26
7 Mar 2026$3.26
8 Mar 2026$3.26
9 Mar 2026$3.26
10 Mar 2026$3.26
11 Mar 2026$3.26
12 Mar 2026$3.26
13 Mar 2026$3.26
14 Mar 2026$3.26
15 Mar 2026$3.26
16 Mar 2026$3.26
17 Mar 2026$3.26
18 Mar 2026$3.26
19 Mar 2026$3.26
20 Mar 2026$3.26
21 Mar 2026$3.26
22 Mar 2026$3.26
23 Mar 2026$3.26
24 Mar 2026$3.26
25 Mar 2026$3.26
26 Mar 2026$3.26
27 Mar 2026$3.26
28 Mar 2026$3.26
29 Mar 2026$2.57
30 Mar 2026$2.57
31 Mar 2026$2.57
1 Apr 2026$2.57
2 Apr 2026$2.57
3 Apr 2026$2.57
4 Apr 2026$2.57
5 Apr 2026$2.57
6 Apr 2026$2.57
8 Apr 2026$2.57
9 Apr 2026$2.57
10 Apr 2026$2.57
11 Apr 2026$2.57
12 Apr 2026$2.57
13 Apr 2026$2.57
14 Apr 2026$2.57
15 Apr 2026$2.57
16 Apr 2026$2.57
17 Apr 2026$2.57
18 Apr 2026$2.57
19 Apr 2026$2.57
20 Apr 2026$2.57
21 Apr 2026$2.57
22 Apr 2026$2.57
23 Apr 2026$2.57
24 Apr 2026$2.57
25 Apr 2026$2.57
26 Apr 2026$2.57
27 Apr 2026$2.57
28 Apr 2026$2.57
29 Apr 2026$2.57
30 Apr 2026$2.57
1 May 2026$2.57
2 May 2026$2.57
3 May 2026$2.57
4 May 2026$2.57
5 May 2026$2.57
6 May 2026$2.57
7 May 2026$2.57
8 May 2026$2.57
9 May 2026$2.57
10 May 2026$2.57
11 May 2026$2.57
12 May 2026$2.57
13 May 2026$2.57
14 May 2026$2.57
15 May 2026$2.57
16 May 2026$2.57
17 May 2026$2.57
18 May 2026$2.57
19 May 2026$2.57
20 May 2026$2.57
21 May 2026$2.57
22 May 2026$2.57
23 May 2026$2.57
24 May 2026$2.57
25 May 2026$2.57
26 May 2026$2.57
27 May 2026$2.57
28 May 2026$2.57
29 May 2026$2.57
30 May 2026$2.57
31 May 2026$2.57
1 Jun 2026$2.57
2 Jun 2026$2.57
3 Jun 2026$2.22
4 Jun 2026$2.22
5 Jun 2026$2.22
6 Jun 2026$2.22
7 Jun 2026$2.22
8 Jun 2026$2.22
9 Jun 2026$2.22
10 Jun 2026$2.22
11 Jun 2026$2.22
12 Jun 2026$2.22
13 Jun 2026$2.22
14 Jun 2026$2.22
15 Jun 2026$2.22
16 Jun 2026$2.22
17 Jun 2026$2.22
18 Jun 2026$2.22
19 Jun 2026$2.22
20 Jun 2026$2.22
21 Jun 2026$2.22
22 Jun 2026$2.22
23 Jun 2026$2.22
24 Jun 2026$2.22
25 Jun 2026$2.81
26 Jun 2026$2.81
27 Jun 2026$2.81
28 Jun 2026$2.81
29 Jun 2026$2.81
30 Jun 2026$2.81
1 Jul 2026$2.81
2 Jul 2026$2.81
3 Jul 2026$2.81
4 Jul 2026$2.81
5 Jul 2026$2.81
6 Jul 2026$2.81
7 Jul 2026$2.81
8 Jul 2026$2.81
9 Jul 2026$2.81
10 Jul 2026$2.81
11 Jul 2026$2.81
12 Jul 2026$2.81
13 Jul 2026$2.81
14 Jul 2026$2.81
15 Jul 2026$2.81
16 Jul 2026$2.81
17 Jul 2026$2.81
18 Jul 2026$2.81
19 Jul 2026$2.81
20 Jul 2026$2.81
21 Jul 2026$2.81
22 Jul 2026$2.81
23 Jul 2026$2.81
24 Jul 2026$2.81
25 Jul 2026$2.81
26 Jul 2026$2.81
27 Jul 2026$2.81
28 Jul 2026$2.81
29 Jul 2026$2.81
30 Jul 2026$2.81
31 Jul 2026$2.81
1 Aug 2026$2.81
2 Aug 2026$2.81
3 Aug 2026$2.81
4 Aug 2026$2.81
5 Aug 2026$2.81
6 Aug 2026$2.81
7 Aug 2026$2.81
8 Aug 2026$2.81
9 Aug 2026$2.81
10 Aug 2026$2.74
11 Aug 2026$3.36
12 Aug 2026$3.36
13 Aug 2026$3.36
14 Aug 2026$3.36
15 Aug 2026$3.36
16 Aug 2026$3.36
17 Aug 2026$3.36
18 Aug 2026$3.36
19 Aug 2026$3.36
20 Aug 2026$3.36
21 Aug 2026$3.36
22 Aug 2026$3.36
23 Aug 2026$3.36
24 Aug 2026$3.36
25 Aug 2026$3.36
26 Aug 2026$3.36
27 Aug 2026$3.36
28 Aug 2026$3.36
29 Aug 2026$3.36
30 Aug 2026$3.36
31 Aug 2026$3.36
1 Sept 2026$3.36
2 Sept 2026$3.36
3 Sept 2026$3.36
4 Sept 2026$3.36
5 Sept 2026$3.36
6 Sept 2026$3.36
7 Sept 2026$3.36
8 Sept 2026$3.36
9 Sept 2026$3.36
10 Sept 2026$3.36
11 Sept 2026$3.36
12 Sept 2026$3.36
13 Sept 2026$3.36
14 Sept 2026$3.36
15 Sept 2026$3.36
17 Sept 2026$2.77
20 Sept 2026$2.77
23 Sept 2026$2.89
26 Sept 2026$2.89
29 Sept 2026$2.89
2 Oct 2026$2.89
5 Oct 2026$2.89
8 Oct 2026$2.89
15 Oct 2026$3.13
16 Oct 2026$3.13
17 Oct 2026$3.13
20 Oct 2026$3.13
21 Oct 2026$3.13
23 Oct 2026$3.13
24 Oct 2026$3.13
Period high$13.00
Period low$2.22
Period average$4.30
Recorded points719

Sales History

0 sold · all variants(30D)

Sales recorded · 21 Sept 2026 – 20 Oct 2026. Sales are grouped into reporting periods; the final date is the latest available data.

Showing Foil - Near Mint - English

Click a bar to view full breakdown
View recorded sales data
Reporting periods for Foil - Near Mint - English. Missing values are shown as a dash.
DateUnits soldTransactionsMarket priceDetails
23/09/202600$2.89View sales
26/09/202600$2.89View sales
29/09/202600$2.89View sales
02/10/202600$2.89View sales
05/10/202600$2.89View sales
08/10/202600$2.89View sales
11/10/202600$2.89View sales
14/10/202600$2.89View sales
17/10/202600$2.89View sales
20/10/202600$2.89View sales
0Units sold · selected condition
0Transactions · selected condition
$2.89Average recorded market price
—Lowest Sale
—Highest Sale

Average recorded market price is the simple mean of reporting periods with a positive market price; it is not weighted by sales volume. A dash means no usable observation is available.