Identify and count consecutive negative figures in a dataset

Hi there,
I am currently trying to identify and count multiple series of negative figures separately in a dataset. I have copied an example below, I need an annual tally of the length of each set of negative figures.

10/04/2002 -25.89999
11/04/2002 -23.78478
12/04/2002 -9.33111
13/04/2002 -0.58254 4
14/04/2002 3.33667
15/04/2002 8.56847
16/04/2002 12.43831
17/04/2002 11.18699
18/04/2002 9.47207
19/04/2002 7.91838
20/04/2002 7.30859
21/04/2002 5.71721
22/04/2002 4.1068
23/04/2002 2.70522
24/04/2002 1.4354
25/04/2002 0.29924
26/04/2002 -1.01067
27/04/2002 -2.00181
28/04/2002 -3.15657
29/04/2002 -4.19175
30/04/2002 -5.51461
01/05/2002 -6.15286
02/05/2002 -6.99173
03/05/2002 -7.81675
04/05/2002 -8.58129
05/05/2002 -9.12188 10

Is there a formula that can count consecutive negative values in segments, skipping over the positive values? As to avoid manually counting the periods (eg. 4 and 10)