@ria_rose Hi Ria, good to see you are still here 
The RBNZ cut the interest rate and it proved a surprise, hence the big NZD drop:
Also, there is a strong correlation between dairy prices and the Kiwi Dollar: your chart starts from the beginning of May, and if you look at the Global Dairy Trade auctions (held every two weeks in Auckland, NZ) since the.second half.of May you will see a lot of negative results:
(See: GDT Events Results » GlobalDairyTrade )
The last thing to look at is dry milk (powdered milk) futures quotes, from CME, as NZ is a massive exporter of dry milk to China (to make baby milk):
In this screenshot from May onward, it is almost impossible not to notice the strong resemblance to the NZD chart that you posted, with the added information of real volume (bars at the bottom of the chart) showing intense selling matched by strong down-trending.
The source was the 2019 September-expiry non-fat dry milk CME Futures contracts, which you can find here:
https://www.cmegroup.com/apps/cmegroup/widgets/productLibs/esignal-charts.html?code=GNF&title=SEP_2019_Nonfat_Dry_Milk_&type=p&venue=0&monthYear=U9&year=2019&exchangeCode=XCME
I hope that this will help you a little bit 
PipMeHappy